GMaps integration

Added:
- Google Maps integration
- Unique username validator
Merge branch 'master' of https://github.com/naorbo/BikeChallange

Conflicts:
	BikeChallengeApp/bin/BikeChallengeApp.dll
	BikeChallengeApp/bin/BikeChallengeApp.pdb
	BikeChallengeApp/obj/Debug/BikeChallengeApp.csprojResolveAssemblyReference.cache
	BikeChallengeApp/obj/Debug/BikeChallengeApp.dll
	BikeChallengeApp/obj/Debug/BikeChallengeApp.pdb
	BikeChallengeApp/obj/Debug/DesignTimeResolveAssemblyReferencesInput.cache