Move to Aegis for easier and prettier command code

[YTG1234]

Aegis is a DSL, wrapper around Brigadier that has a nicer format and look.

This PR moves Kommander's commands over to Aegis' DSL system.

This conflicts with #7 , I'm not sure if it conflicts with #2 .
I will fix all my PRs when one gets merged.

[gdude2002]

This doesn't seem like much of an improvement at all — looks like it's just brigadier but with receiver functions. What's the real advantage here? Some of the commands given are actually longer with this library.

Also, is Jitpack really the only option?

[YTG1234]

This doesn't seem like much of an improvement at all — looks like it's just brigadier but with receiver functions. What's the real advantage here?

I guess it's just a matter of personal preference, but I think the structure of the command builder is nicer with this library, And it's made specifically for Kotlin.

Also, is Jitpack really the only option?

Unfortunately, I couldn't find any other way to pull it down.