[WIP] Redo Bot Configuration and Connection Manager

New Features:
- [x] Multi-server support
    - [x] Per-server configuration overriding
- [x] Threaded event handlers
- [ ] Configuration file inclusion?

Changes:
- The configuration section `[server]` is now `[server.<name>]`, replacing `<name>` with something unique that will be used to refer to the server.
    - To override other settings, just set them again under the section `[server.<name>.<section>]`, replacing `<name>` with the name of the server you want the override to affect and `<section>` with the original section name.