Started on screen decompilation

Translated most of the basic commands, other commands are replaced by
python blocks if not known.
typo in license
Support for all screen statements & comments

Also fixed pause 0 spam
small multiline attr fix, and duplicate elif fix
even more imports and a for in: screenlang fix.

accidentally split in the wrong order.
BUGFIXES: THE FIXING

just a lot of random things in screen parsing and ATL parsing mostly.
Merge pull request #6 from CensoredUsername/master

screens will now be decompiled to screen language. Also a lot of general bugfixes.