fix comment typo
clean library to prep for refactoring
Merge branch 'refactor_LibraryCleanup' into refactor
Merge remote-tracking branch 'remotes/upstream/refactor' into refactor
finished refactor of Library.hs
Merge remote-tracking branch 'upstream/refactor' into refactor

Conflicts:
	core/src/Strappy/Library.hs
Expr.hs exports conversion utilities
Added a non-monadic wrapper that evaluates the loglikelihood of an expression in any empty context. Renamed a few functions.