[TxMt] GTD Bundle sort command

[Mike Mellor]

I just uploaded a new GTD sort command as part of the GTD bundle.   
The code may not be pretty, but I think it works.  To use it, you  
need to create a contexts.gtd file in your GTD project.  This file  
holds the contexts that the sort function uses to sort a file.  There  
are several items in the file that don't do anything yet, but I'm  
hoping to keep the file stable as I add functionaility.  As always,  
feedback is encouraged!

Alaskamike