Improve Home Assistant MQTT Discovery.

[Tmaxxrox97]

• Switch to device discovery over sensor discovery
• Add ability to add additional discovery options

[Tmaxxrox97]

Whoops... Didn't mean to submit this yet but I think for the most part it could be used. There are still some things that could probably be cleaned up.

I wanted to add the ability to add additional discovery options to home assistant such as the state_class, device_class, and whether the entity is enabled by default or not to help with making the device a bit clearer in Home Assistant.

I figured it would also be beneficial to switch to Device discovery rather than entity discovery since we can send batches of entities rather than individually.