Finite State Machines for guidance

Here's a little re-implementation of guidance regex grammars using finite state machines (implemented on top of interegular). This adds a couple of features that guidance does not yet support, including using curly braces to indicate number of occurences, (some) lookaheads, and potentially fixing some issues with negations.

See tests for example usage

Instead of

from guidance import regex

try

from pastafarian import regex

Note that this package depends on some things that are currently not in a released version of guidance, including grammars implemented using mutual recursion. So please install guidance from source using the most up-to-date version.