* Make our regexes more permissive (though still separated out for
readability, despite being identical)
* Add a helper that will improve readability while sanity testing our
regex results.
Add tests that ensure that image syntax resolves to API input the way we
want it to.
Add a lot of different input forms for images, to more closely map to
what the API accepts, so anything that's valid input to the API should
also be valid input in a config.
Stop resolving image families to specific image URLs, allowing things
like instance templates to evolve over time as new images are pushed.
