cleanup query_string documentation

- Consistently use 'query parameter' terminology instead of query_string
  and query_filter, which are completely meaningless remnants from when
  this was a shared google doc of api notes.
- Rewrite all the available query parameters as sorted markdown lists

Change-Id: I2dbd2014bb86884d49e67a46dcc835473a4179b1
Merge "cleanup query_string documentation"