Added ANSI coloring to haxelib help command

[ninjamuffin99]

Will be looking for a bit more feedback on cleanup, but added ANSI coloring to the haxelib help command

Things yet to implement

• Use the same environment variable that hxcpp uses to disable ansi codes for coloring
• I based the ansi related code off the haxe-strings implementation with a few changes, will poke around to make sure it's credited / licensed properly

ansi usage is to add

using haxelib.client.ansi.Ansi;

and then on any string you can add ANSI via one of the functions from Ansi.hx with the enums from AnsiColor.hx or AnsiTextAttribute.hx
Cli.print("epic".fg(RED));
will print
epic in red