Added classes used when retrieving login responses instead of working with a dictionary.
Changed several method implementations to use the newly added classes.
Changed Login action to make use of the new return values given by the WebApiHelper.
Added BaseController with a protected WebApiHelper instance.
Added custom AppSetting with the base url to the WebApi.
Made use of the WebApiHelper in the BaseController.
Added instance variable of the RestClient, instead of creating an instance over and over again.
Replace Errors property with 3 new properties: Error, ErrorDescription and ErrorUri.
Changed implementation of Login method to use the newly added ErrorDescription property of the WebApiHelper class.
Merge branch 'feature/apihelper-controllers' into develop, containing a refactored WebApiHelper and refactored implementation of multiple controllers.