Two bug fixes + code simplification improving performance
Support for more general demography has been added.
A branch of the code involving making "gamete lookup tables" has been removed. This does not affect the API. It does simplify the code base and improve run-time performance. These lookups could be removed because the "recycling" introduced in 0.4.4 made them irrelevant, and go from something that helped performance to a performance hindrance.