Add BU and MIT to list of schools with similar projects

Googled some schools around the Boston area. These were the only two I found. Northeastern has _something_ called "API Strategy" or Northeastern Create or something but I couldn't find any other info on it and I'm not even sure either of those things actually exists or are relevant. Maybe remainders of scrapped plans?

README.md

@@ -50,4 +50,6 @@ Check out [CONTRIBUTING.md](https://github.com/simon-andrews/umass-toolkit/blob/
 Similar projects
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 Know of a similar project at another institution? Link to it here!
- * University of Pennsylvania: [PennSDK (Python)](https://github.com/pennlabs/penn-sdk-python)
+ * Boston University: [BU API Registry](https://webapi.bu.edu/)
+ * Massachusetts Institute of Technology: [MIT Developer Connection](https://ist.mit.edu/apis)
+ * University of Pennsylvania: [PennSDK](https://github.com/pennlabs/penn-sdk-python)