Feature Phone mode

[kosamari]

This PR adds mostly key events and the key shortcut indicators for Feature phone users. This changes bunch of things to make experience on feature phone more enjoyable.

• * key and # are used as soft key. * for menu items on the left, # for items on right.
• adds square key icons to indicate buttons also have key short cut
• no fullscreen mode exposed
• bottom bar has significant change in design to fit in a small screen.

Goal of this PR is to minimize the time user have to use mouse to navigate.

Fixes: #311 Fixes: #374

This PR does not fix focus issue and will track in separate issue.

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