dashboard: Replace three-step sed replace by proper template replace

Was not easy but
http://stackoverflow.com/questions/4937792/using-variables-inside-a-bash-heredoc
http://stackoverflow.com/questions/415677/how-to-replace-placeholders-in-a-text-file
http://stackoverflow.com/questions/1167746/how-to-assign-a-heredoc-value-to-a-variable-in-bash

helped.

Also making the header content configurable so that we can extend the template
content with other sections, too.

bin/dashboard

@@ -22,8 +22,11 @@ decrease_header() {
 closed_html=$($OPENQA_REVIEW $GLOBAL_PARAMS --save --save-dir="$tmp" -f closed | decrease_header | markdown)
 unassigned_html=$($OPENQA_REVIEW $GLOBAL_PARAMS --load --load-dir="$tmp" -f unassigned | decrease_header | markdown)
 
-sed '/TPL_OPENQA_CONTENT/q' $TPL | head -n -1 > $OUT
-cat >> $OUT <<EOF
+TPL_OPENQA_HEADER_LINKS='
+<p><a href="#closed_box">» Closed bugs</a></p>
+<p><a href="#unassigned_box">» Unassigned bugs</a></p>
+'
+TPL_OPENQA_CONTENT=$(cat <<EOF
 <div class="panel panel-default" id="closed_box">
     <div class="panel-heading" style="font-weight: bold;">
         Closed Bugs
@@ -42,5 +45,11 @@ cat >> $OUT <<EOF
     </div>
 </div>
 EOF
+)
+
+eval "cat <<EOF
+$(<$TPL)
+EOF
+" 2> /dev/null > $OUT
+
 
-sed '1,/TPL_OPENQA_CONTENT/d' $TPL >> $OUT

dashboard_files/dashboard.html.in

@@ -62,8 +62,7 @@
         <div class="col-md-10">
             <h2>openQA review report for openqa.suse.de</h2>
 
-<p><a href="#closed_box">» Closed bugs</a></p>
-<p><a href="#unassigned_box">» Unassigned bugs</a></p>
+            ${TPL_OPENQA_HEADER_LINKS}
 
         </div>
 
@@ -78,7 +77,7 @@
     </div>
 </div>
 
-TPL_OPENQA_CONTENT
+${TPL_OPENQA_CONTENT}
 
       </div>