Added new rebinner and updated LevelTwo.java to call it correctly.
Improved some handling of fill values. Added a FILL_DOUBLE constant and made changes where appropriate. Finished rebinner. Uncommented the doGpsCdf() routine that was removed during debugging.
Added accumulation offsets to the Constants.java class. Subtracted accumulation times from L1 and L2 epoch variables.
Merge pull request #45 from wrexroad/master

New rebinner for spectra and accumulation time offsets for epoch.