Refactor - WalletAssets and Config abstraction

Initial Omni refactor, abstracted config.js into it's own module, defined variables as module constants and value factories.
Abstracted WalletAssetsFormController into a Service, this returns a Singleton instance of the defined function that has all the methods and values to manage WalletAssets.

No further implementation on the service yet, this is the base for other pages to implement.