New features for channels

This is just a collection of new features I think we should have for channels.

Channel prefix changing

I think it would be cool if we could change whether # would be before the name of channels, maybe if it was in X category, it would have $ before it's name instead

Voice channel mentioning

We can mention text channels, so why not voice channels? We should be able to mention voice channels, using the standard #.

Channel (and category) Color changing

It would be great if we could change the color of channel names, and if we could do the same with categories, it would be even better