Add rest server

Creates REST endpoints to support governance log manipulation as outlined in [Issue 1](https://github.com/courage-labs/freefrog/issues/1). Still missing user CRUD, anchor circle CRUD, and user -> role assignment.
The language here isn't helpful to a customer. How about "should not respond to application/json" or something? Also, we should probably def these magic numbers instead of using the raw codes. It's kind of annoying to have to keep referring back to the HTTP spec. The codes are defined in the HttpClient library (http://hc.apache.org/httpcomponents-core-ga/httpcore/apidocs/org/apache/http/HttpStatus.html) but I can't find them in http-client anywhere.