Review step-by-step guide

[frankiejol]

Step by step guide for first time users.

• [x] Remove button step-by-step guide on main screen
• [ ] Add an entry for the guide at Help menu
• [x] Add a config field to enable the guide, disabled by default
• [ ] Show the guide for the users only the first time they login
• [x] Allow the users to exit the guide at any step

[fv3rdugo]

It was necessary to apply a missing cherry pick to 0.2.15 branch.

• users can exit the guide at any step with ESC key
• now, guide is disabled by default the other points soon available!