Rename layouts
Also switch with ENTER
.gitignore
Add licence and link to source
Change HTML title: Breath Tuner -> BreathTuner
nav css
Increase double key press protection time to 2s

It now matches the red zone.
Refactor
Render remainder when switching or stopping
Rename: drawChart() -> renderTime()
setInterval -> setTimeout
TODO
Fix: first space inserted is 1px too much
Rm unnecessary Math.floor

tCursorNextPos is always a multiple of minMS.
Implement xCursor
Execute updateCanvasPosition() only when necessary

Execute it between full-breaths, but not between half-breaths.
Merge updateXCursor() into updateCanvasPosition()
Rename var: yPos -> yCursor
Replace xPos & yPos with xCursor & yCursor
Indentation