Initial commit of the new method "prayer"

The new method is a "clean-room" implementation of the prayer times
and qibla direction calculations. This new implementation uses
simpler but approximate methods. This should make the code much
simpler and easier to maintain. The impact on accuracy is still
to be determined. Please NOTE that this is still WIP and far from
being complete
Umm Al-Qura uses a fajr angle of 18 degrees, not 18.5. You should also add the "gulf region" method with a fajr angle of 19.5 and an Isha offset of 90 minutes.