added provider inheritance
dropped unused random methods
dropped unneeded bottom overrides
flipped type parameters

emphasizes base combinatorial type over container type
moved alleles to constructor
use combinatorial traits in the wild
added fixed size
fixed combinators do not define mutate locally
do not allow fixed containers to vary
do not allow variable containers to vary
implemented fixed generator
factor out container type for maximum nerdity
what does this do?
push execution context to the surface