Fix CompilerDefines fields

[RblSb]

No description provided.

[RobDangerous]

That's a very "for my use only" pull request :-P
Let's replace '-' with '_' and prepend '_' to keywords.

[RblSb]

This is more for hxcpp use pr :)
Replacement need field checking for duplicates. Will see how can i check added fields or use StringMap. But you probably don't need if (CompilerDefines._static != null), when you can use #if, same for other bool defines, doesn't? This is why pr is fine.

[RblSb]

HaxeFoundation/haxe#5002 is fixed, so Kha probably broken with current behavior, so i complete this thing.

[RobDangerous]

I fixed it so much, it will never ever be a problem again (also added an updates.md and referenced this pull request in there).

[RblSb]

I mostly interested in this class for window name instead of default:
https://github.com/Kode/Kha/blob/master/Sources/kha/System.hx#L7
So you don't need to set same project name in System.start, only in khafile.js. Can we move Macros.hx to kha.internal and set title = Macros.projectName() as default value?

[RobDangerous]

I don't think the Window title should be a define, just pass it manually.

[RblSb]

That's sad, then this line should be removed https://github.com/Kode/khamake/blob/master/src/main.ts#L120

[RobDangerous]

But using that line you can write some code which sets the window title to the project name.

[RblSb]

But you say that this should not be a define :) If you fine with define in khamake then i'm good, but i can also add this define manually in khafile, without khamake dependency.

[RobDangerous]

It's already there and today I don't feel like removing more things.