Added new API action to change credentials.
Implemented the SetCredentials API action.
Added test cases to test the SetCredentials API action.
Implemented GetResource.
Refactored the SetCredentials API action.
Added support to the Web UI to change username/password.
Web UI now shows alert if user was not able to change username/password. This needs to be beautified in the future.
Merge branch 'feature/setcredentials' into develop