Two reasons to change:
1. More complience to Foursqare API, they expects ?v=YYYYMMDD instead of ?YYYYMMDD, we need to clearly define parameters to avoid future confusions
2. It's safer to rely on API version which is closer to module development time.  I think we need someone to check API changes complience
Merge pull request #152 from pavlyuts/ForSquare_Fix

More correct code for Foursquare API chages