reducing allocations, increasing clarity by removing some magic numbers
probably can rewrite some of the evo loading/checking for even less, but
good for now.
reduce nesting (evo.RequiresLevelUp is checked twice, only check once
and handle path)
compact some methods
seal some classes
add a little xmldoc to exposed members
Rename "Flag" to "Method"; isn't used besides for indicating the evo
Method.
Remove some unnecessary duplicate checks
- always >=1 in chain at start
- mostEvolved already checked for > maxspeciesgen
