Change playback time interval setting : only one parameter instead of two
and do not allow values witch are not sub-multiples of the original file
intervall to ovoid inconsistencies . Also make it more understandable
to common users.(#FS 1337)
Add Waves period in Weather Table
Correct playback regressions
Merge pull request #96 from Ptizef/master

Change Setting logic for playback time interval setting and add waves period in weather table