Changes since 2.0:
- fix broken functional key layout for tablets
- only show language switch key when there is something to switch to (#897)
- make default colors for "all colors" setting random instead of gray (#903)
- allow customizing start lag for gestures during typing, by @devycarol (#882, #894)
- allow customizing currency keys (#353)
- reduce long-press time for shift -> caps lock, by @devycarol (#924, #923)
- extend superscript popups in number row and symbols layout, by @b02860de585071a2 (#902, #901)
- minor fixes and improvements