investigate adding support for themes

[cryptk]

There's no support in the underlying library yet for interacting with themes. Assuming that themes are an actual concept that exists in the API, and not just the application firing off multiple set equipment commands in sequence, we should at least be able to add support for applying a theme via a button entity.

Needs cryptk/python-omnilogic-local/issues/1 and cryptk/python-omnilogic-local/issues/2 to be completed to support this