Live load/unload of plugins

[VictorioBerra]

I realize the dependencies make this very difficult. But we could resolve the graph, and load/reload everything down the chain one at a time and then bring them back. Not sure how difficult that would be.

We would want a programmatic API like client.plugin.load("admin") and reload, unload.

I desire this personally because I could have plugins self update and never take my bot offline if this existed, and also SupyBot has it and it's pretty darn useful.