Compile Progress

[NeeEoo]

This changes the compile header to be

Compiling group: haxe (2997 files)

and adds a small tag saying the progress of the compilation

[SorbetLover]

Bro is cooking

[MAJigsaw77]

I think it should look better if you don't add that space when is for example [ 0.8%].

[Simn]

The space is important for alignment:

[9.8%]
[9.9%]
[10.0%] <-- asdf

[mcagabe19]

and it'd better if it print num file(s) instead of num files