Add commands with multiple targets to Assist

[synesthesiam]

Add commands like "turn on the lights and fans" or "set brightness of overhead light and standing light to 50%".
These are distinct from commands like "turn on the lights and start the music", which perform more than one intent.

Some things to consider:

• Most intents already support multiple values for slots like name, but the intents repo expects a single value right now
• Names with "and" should be prioritized before multiple targets
• How do we handle errors and responses?
• How will this affect Speech-to-Phrase?

[synesthesiam]

hassil PR: OHF-Voice/hassil#234