fix Impl.FoursquareClient request GetUserInfo

1. add `v` parameter to API request. According to https://developer.foursquare.com/overview/versioning
2. `photo` is consists of two parts `prefix` and `suffix` now. Fix `PhotoUri` parsing
Merge pull request #30 from unknownexception/patch-1

Fix Impl.FoursquareClient, add `v` parameter, fix `photo` parsing