Rework menu and tab/screen interface

[hughbris]

The current menu is based on Evothings sample code and could be improved:

• larger items (currently can be difficult to select on small screens)
• more colourful items
• left side burger (?)

Mode switching (e.g. Map/Console/Log/Settings) is primitive and shoehorned into the Evothings-based menu. Ideally modes will be switchable by swiping (refer VLC app). Alternatively a tabbed interface using colour/style mnemonic cues.

[hughbris]

Being surpassed by progress on #8. So far

• burger (RHS)
• tabs with swipe support