Use consistent key-bindings for exit (and return navigation)

[Gituser143]

Currently the following have mixed combinations of exit and return key-bindings:

• Exit from main page (q and ^C)
• Return from coin page to main page (Esc and q and ^C)
• Exit from coin page (Not Set)
• Return from widget to main page (Esc)
• Exit from widget (q and ^C)

A consistent mapping of q and ^C to quit and Esc to return could be implemented. Or maybe using all three to return to previous page and then exit from the main page.