General bug fixes/additions

Started implementation of block contribution view.
Ensured single instance of the application.
Automated cleanup/formatting of code.
Upon fetching JSON data it'll notify the user if the API token is
incorrect.
Stopped an issue of two connections being made at the same time -
onCreate() and onResume() both were calling startJSONFetching(), both
are called upon startup so only onResume's calling is required.