No content on responses without status=200

[GoogleCodeExporter]

There are endpoints in the API that may return useful content even though the 
status is not 200.

E.g. "venues/add" may return 409 with "candidateDuplicateVenues" and a 
"ignoreDuplicatesKey" included in the response.

Try:
https://api.foursquare.com/v2/venues/add?name=Yalla+Yalla&ll=51.516388%2C-0.1387
11&oauth_token=XXXXXX



The lib is currently setting to null any content from responses with code other 
than 200.
See FoursquareApi.class, venuesAdd method, line 862

Original issue reported on code.google.com by victor.b...@glance.cc on 21 Jun 2013 at 1:48