[V2] Whisper implementation

[InzeNL]

Implements the whisper command for TMI and adds tests for it

Also added codestyle files for JetBrains IDEAs to prevent overriding set codestyles

[InzeNL]

Requires implementation of WHISPER event

[InzeNL]

#356 (comment)

Requires implementation of WHISPER event

Implemented in 150b6e6

[Geczy]

can this be merged? whats the hold up @InzeNL

[InzeNL]

@Geczy

Granted I don't know how well this still works, there's no hold up on my side.
It was simply never reviewed by anyone.

I do notice this merges to "old-v2" so I'm not sure how valid the pull request is.