This commit adds a module for a finite state machine. The goal of the
module is to provide a simple, easy to use, and easy to understand
finite state machine. The module is designed to be used in future
loop subsystems. Additionally a state visualizer is provided to
help with understanding the state machine.
This commit fixes outstanding linter issues, that we're not found by
running `make lint` locally. The linter issues were found by running
`docker run -v $(pwd):/build loop-tools golangci-lint run --whole-files`
I added the `revive` to the excludes as it would be to much of a
refactor and IMO seems unneccesary. E.g.
`interface.go:222:6: exported: type name will be used as
loop.LoopInTerms by other packages, and that stutters; consider
calling this InTerms (revive)`. I think `loop.LoopInTerms` is fine.
