Fixed: Client ID input, in the demo module, was too short.

Added a setup screen to the demo, with short instructions on how to enable OAuth for a google API.

Improved the great job done by João Pedro Abreu, to add:

- New action: SetValues to write values into a range of cells

- New test screen for the new SetValues action

- Enhanced error description (all Google API error details available)

- Better encapsulation (better for reuse in your application) in public actions, no Google Auth internals in the public actions parameters

- New icons