[sbml-required] New version

[Lucian S. <lp...@sp...>]

No new validation rules yet, but everything else has been overhauled to 
use the new system, and there is extensive discussion about how 
different packages may interact with this package:

https://docs.google.com/file/d/0B71r5kLs3FliVDZDR2xlLUJOWUk/edit

-Lucian