Fix #3 and add undead join/leave messages

[srnyx]

Description

Made tab and channel topic update a lot more efficiently and added join/leave messages for undead.

Motivation and Context

Fixes #3 Adds more customizability

How Has This Been Tested?

Testes this on the server itself and it works perfectly!

Media:

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [x] I have read the CONTRIBUTING document.
• [x] All new and existing tests passed.