Fix timer nav controller behaviour. Closes #283
Fix timer nav controller behaviour. Closes #283

The attempt to fix the missing start button in cc2295b did more harm
than good. This should fix the logic of the navigation controller for
good.

peeedge/mobile,peeedge/mobile,masterrr/mobile,eatskolnikov/mobile,masterrr/mobile,ZhangLeiCharles/mobile,eatskolnikov/mobile,eatskolnikov/mobile,ZhangLeiCharles/mobile