[gPXE-devel] Minor Scripting Improvements

[Miller, Shao]

Here's a 540-byte-costing patch for 'exit', 'if', ':' and 'goto'.

This version:
- includes usage text for ':' and 'goto'
- allows for dynamic labels (though that's not important)
- does not store labels in settings
- scans the current script for labels

I would certainly appreciate code review from other developers.  Thanks!

- Shao Miller

[1]
http://git.etherboot.org/?p=people/sha0/gpxe.git;a=commitdiff;h=50fea43a
125d8cc8adfdcaa459d492ff0afbe66f