diff --git a/docs_src/package-lock.json b/docs_src/package-lock.json
index e12a8f9c..a13b7417 100644
--- a/docs_src/package-lock.json
+++ b/docs_src/package-lock.json
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-      "integrity": "sha1-32BBeABfUi8V60SQ5yR6G/qmf4w="
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@@ -3452,12 +3591,12 @@
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-      "resolved": "https://registry.npmjs.org/proxy-addr/-/proxy-addr-2.0.4.tgz",
-      "integrity": "sha512-5erio2h9jp5CHGwcybmxmVqHmnCBZeewlfJ0pex+UW7Qny7OOZXTtH56TGNyBizkgiOwhJtMKrVzDTeKcySZwA==",
+      "version": "2.0.7",
+      "resolved": "https://registry.npmjs.org/proxy-addr/-/proxy-addr-2.0.7.tgz",
+      "integrity": "sha512-llQsMLSUDUPT44jdrU/O37qlnifitDP+ZwrmmZcoSKyLKvtZxpyV0n2/bD/N4tBAAZ/gJEdZU7KMraoK1+XYAg==",
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-        "forwarded": "~0.1.2",
-        "ipaddr.js": "1.8.0"
+        "forwarded": "0.2.0",
+        "ipaddr.js": "1.9.1"
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@@ -3527,9 +3666,9 @@
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-      "integrity": "sha1-9JvmtIeJTdxA3MlKMi9hEJLgDV4="
+      "version": "1.2.1",
+      "resolved": "https://registry.npmjs.org/range-parser/-/range-parser-1.2.1.tgz",
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@@ -3883,9 +4022,9 @@
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-      "resolved": "https://registry.npmjs.org/send/-/send-0.16.2.tgz",
-      "integrity": "sha512-E64YFPUssFHEFBvpbbjr44NCLtI1AohxQ8ZSiJjQLskAdKuriYEP6VyGEsRDH8ScozGpkaX1BGvhanqCwkcEZw==",
+      "version": "0.17.2",
+      "resolved": "https://registry.npmjs.org/send/-/send-0.17.2.tgz",
+      "integrity": "sha512-UJYB6wFSJE3G00nEivR5rgWp8c2xXvJ3OPWPhmuteU0IKj8nKbG3DrjiOmLwpnHGYWAVwA69zmTm++YG0Hmwww==",
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@@ -3894,18 +4033,50 @@
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         "fresh": "0.5.2",
-        "http-errors": "~1.6.2",
-        "mime": "1.4.1",
-        "ms": "2.0.0",
+        "http-errors": "1.8.1",
+        "mime": "1.6.0",
+        "ms": "2.1.3",
         "on-finished": "~2.3.0",
-        "range-parser": "~1.2.0",
-        "statuses": "~1.4.0"
+        "range-parser": "~1.2.1",
+        "statuses": "~1.5.0"
       },
       "dependencies": {
+        "http-errors": {
+          "version": "1.8.1",
+          "resolved": "https://registry.npmjs.org/http-errors/-/http-errors-1.8.1.tgz",
+          "integrity": "sha512-Kpk9Sm7NmI+RHhnj6OIWDI1d6fIoFAtFt9RLaTMRlg/8w49juAStsrBgp0Dp4OdxdVbRIeKhtCUvoi/RuAhO4g==",
+          "requires": {
+            "depd": "~1.1.2",
+            "inherits": "2.0.4",
+            "setprototypeof": "1.2.0",
+            "statuses": ">= 1.5.0 < 2",
+            "toidentifier": "1.0.1"
+          }
+        },
+        "inherits": {
+          "version": "2.0.4",
+          "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz",
+          "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ=="
+        },
         "mime": {
-          "version": "1.4.1",
-          "resolved": "https://registry.npmjs.org/mime/-/mime-1.4.1.tgz",
-          "integrity": "sha512-KI1+qOZu5DcW6wayYHSzR/tXKCDC5Om4s1z2QJjDULzLcmf3DvzS7oluY4HCTrc+9FiKmWUgeNLg7W3uIQvxtQ=="
+          "version": "1.6.0",
+          "resolved": "https://registry.npmjs.org/mime/-/mime-1.6.0.tgz",
+          "integrity": "sha512-x0Vn8spI+wuJ1O6S7gnbaQg8Pxh4NNHb7KSINmEWKiPE4RKOplvijn+NkmYmmRgP68mc70j2EbeTFRsrswaQeg=="
+        },
+        "ms": {
+          "version": "2.1.3",
+          "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.3.tgz",
+          "integrity": "sha512-6FlzubTLZG3J2a/NVCAleEhjzq5oxgHyaCU9yYXvcLsvoVaHJq/s5xXI6/XXP6tz7R9xAOtHnSO/tXtF3WRTlA=="
+        },
+        "setprototypeof": {
+          "version": "1.2.0",
+          "resolved": "https://registry.npmjs.org/setprototypeof/-/setprototypeof-1.2.0.tgz",
+          "integrity": "sha512-E5LDX7Wrp85Kil5bhZv46j8jOeboKq5JMmYM3gVGdGH8xFpPWXUMsNrlODCrkoxMEeNi/XZIwuRvY4XNwYMJpw=="
+        },
+        "statuses": {
+          "version": "1.5.0",
+          "resolved": "https://registry.npmjs.org/statuses/-/statuses-1.5.0.tgz",
+          "integrity": "sha512-OpZ3zP+jT1PI7I8nemJX4AKmAX070ZkYPVWV/AaKTJl+tXCTGyVdC1a4SL8RUQYEwk/f34ZX8UTykN68FwrqAA=="
         }
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@@ -3916,14 +4087,21 @@
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     "serve-static": {
-      "version": "1.13.2",
-      "resolved": "https://registry.npmjs.org/serve-static/-/serve-static-1.13.2.tgz",
-      "integrity": "sha512-p/tdJrO4U387R9oMjb1oj7qSMaMfmOyd4j9hOFoxZe2baQszgHcSWjuya/CiT5kgZZKRudHNOA0pYXOl8rQ5nw==",
+      "version": "1.14.2",
+      "resolved": "https://registry.npmjs.org/serve-static/-/serve-static-1.14.2.tgz",
+      "integrity": "sha512-+TMNA9AFxUEGuC0z2mevogSnn9MXKb4fa7ngeRMJaaGv8vTwnIEkKi+QGvPt33HSnf8pRS+WGM0EbMtCJLKMBQ==",
       "requires": {
         "encodeurl": "~1.0.2",
         "escape-html": "~1.0.3",
-        "parseurl": "~1.3.2",
-        "send": "0.16.2"
+        "parseurl": "~1.3.3",
+        "send": "0.17.2"
+      },
+      "dependencies": {
+        "parseurl": {
+          "version": "1.3.3",
+          "resolved": "https://registry.npmjs.org/parseurl/-/parseurl-1.3.3.tgz",
+          "integrity": "sha512-CiyeOxFT/JZyN5m0z9PfXw4SCBJ6Sygz1Dpl0wqjlhDEGGBP1GnsUVEL0p63hoG1fcj3fHynXi9NYO4nWOL+qQ=="
+        }
       }
     },
     "session-file-store": {
@@ -4357,6 +4535,11 @@
       "integrity": "sha1-3F5pjL0HkmW8c+A3doGk5Og/YW4=",
       "dev": true
     },
+    "toidentifier": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/toidentifier/-/toidentifier-1.0.1.tgz",
+      "integrity": "sha512-o5sSPKEkg/DIQNmH43V0/uerLrpzVedkUh8tGNvaeXpfpuwjKenlSox/2O/BTlZUtEe+JG7s5YhEz608PlAHRA=="
+    },
     "tslib": {
       "version": "1.9.3",
       "resolved": "https://registry.npmjs.org/tslib/-/tslib-1.9.3.tgz",
@@ -4396,12 +4579,27 @@
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-      "resolved": "https://registry.npmjs.org/type-is/-/type-is-1.6.16.tgz",
-      "integrity": "sha512-HRkVv/5qY2G6I8iab9cI7v1bOIdhm94dVjQCPFElW9W+3GeDOSHmy2EBYe4VTApuzolPcmgFTN3ftVJRKR2J9Q==",
+      "version": "1.6.18",
+      "resolved": "https://registry.npmjs.org/type-is/-/type-is-1.6.18.tgz",
+      "integrity": "sha512-TkRKr9sUTxEH8MdfuCSP7VizJyzRNMjj2J2do2Jr3Kym598JVdEksuzPQCnlFPW4ky9Q+iA+ma9BGm06XQBy8g==",
       "requires": {
         "media-typer": "0.3.0",
-        "mime-types": "~2.1.18"
+        "mime-types": "~2.1.24"
+      },
+      "dependencies": {
+        "mime-db": {
+          "version": "1.52.0",
+          "resolved": "https://registry.npmjs.org/mime-db/-/mime-db-1.52.0.tgz",
+          "integrity": "sha512-sPU4uV7dYlvtWJxwwxHD0PuihVNiE7TyAbQ5SWxDCB9mUYvOgroQOwYQQOKPJ8CIbE+1ETVlOoK1UC2nU3gYvg=="
+        },
+        "mime-types": {
+          "version": "2.1.35",
+          "resolved": "https://registry.npmjs.org/mime-types/-/mime-types-2.1.35.tgz",
+          "integrity": "sha512-ZDY+bPm5zTTF+YpCrAU9nK0UgICYPT0QtT1NZWFv4s++TNkcgVaT0g6+4R2uI4MjQjzysHB1zxuWL50hzaeXiw==",
+          "requires": {
+            "mime-db": "1.52.0"
+          }
+        }
       }
     },
     "uglify-js": {
diff --git a/docs_src/package.json b/docs_src/package.json
index c66d981d..6c991f0c 100644
--- a/docs_src/package.json
+++ b/docs_src/package.json
@@ -17,7 +17,7 @@
     "compression": "^1.7.1",
     "devalue": "^2.0.0",
     "do-not-zip": "^1.0.0",
-    "express": "^4.16.4",
+    "express": "^4.17.3",
     "express-session": "^1.15.6",
     "golden-fleece": "^1.0.9",
     "marked": "^0.7.0",