Began implementing fast forward differencing for cubic bezier
Forward differencing setup is working. Need to make it play it well with scanline generation.
Going far enough with FFD, results are not good enough.
Just going to lower level Haskell can make some wonders, cutting allocation by 3
Simplifying decomposition, now faster.
Never forget bang patterns, result are always amazing (like 5* speedup)
Bang patterns, bang patterns everywhere (for primitive decomposition)
Moving forward differencing to it's own file.
First changelog bump
Minor efficiency win using inline pragma.
Merge branch 'ffd'