modified main:get_entry
  - take 'application/json' content_type data as input and return json as output
  - only populate the '_id' in the entries unless the type is specfied (needs work)
modified test.py to pass the get_entry test
modified gridview.js:
  - act as a DataProvider to SlicGrid, e.g. getLength(), getItem(i), and getItemMetaData(i)
  - use synchronous ajax requests to the application on its schema_id, grid_id, and options.uuids[i] to return the requested item via getItem(i)
modified grid_data.html to use GridView as the DataProvider for its SlickGrid instance

ALL TESTS PASS
needs work on the rest of the REST interface to match how get_entry processes and returns json