Merge pull request #38 from RaulLepsa/master

Fixed markUnmarkNSWF method
Refactored method that retrieves the user's information and implemented jUnit test for it
Moved User-related information in the corresponding UserInfo class. Created a constructor that creates a UserInfo object from a JSON object. Removed  unnecessary fields and methods from the User class.
Implemented jUnit test for User.about method and improved it