utl: Add aglDevTools.h

[MonsterDruide1]

This whole thing can either be a class with static functions, or a namespace - according to mangling rules and tests with godbolt. I would think that a class makes a bit more sense, as genMessage(context) seems to be a common function for agl-classes. The getter/setter functions themselves seem to write to static variables, and there are no constructors or instances of DevTools ever kept in a different class.

The functions were "generated" by copying all lines from the function list in IDA, then iteratively adjusting them using Regex to produce functional C-code, as well as conforming our style rules. Return types were manually added whenever it made sense to do so.

---

This change is 

[ThePixelGamer]

Rebase needed

[ThePixelGamer]

LGTM