Fixes #63

With #78 being on hold for now, I submit this request to fix many issues with projected fits. See #63 for details. There's a comment there that lays out the fixes and reasoning behind them. This has been tested as best as I could and I haven't noticed any regression between this and current stable release. However, it has fixed (or apears to fix - I haven't done any hand calculations) stats when projecting boosted fits.