Update TRGoogleMapsAutocompleteItemsSource.m

A macro definition - AFNETWORKING_2 for AFNETWORKING 2.0 support. Corresponding function uses the macro check to support changes in AFNetworking.
Merge pull request #12 from aniketawati/master

Update TRGoogleMapsAutocompleteItemsSource.m for supporting AFNetworking 2.x