Proper max_results handling in eve.utils.parse_request, refactored tests

* fixes issue #43
* parse_request tests now using self.app.test_request_context to pass args and headers (just like in real app)
Merge pull request #44 from Tefnet/5dc46af0edbfccee3c26cffa9c8a9029867ab5b3

Proper max_results handling in eve.utils.parse_request, refactored tests. Closes #43.