Added login via Facebook
Bumped version number
Added support to link an account to Facebook
Added support to unlink an account from Facebook
Added support to fetch linked social accounts
Added support to login with G+
Added support to link an account to G+
Added support to unlink an account to G+
cleaned up code for social
updated readme and cocoapod spec.
Merge commit 'b7ad1b63a6f5ccebcba19b4f0396b49c1f7a0c89'

Conflicts:
	BaasBox-iOS-SDK/BAAClient.h
	BaasBox-iOS-SDK/BAAObject.h
	BaasBoxSDK.podspec