Hi Jason
this was not something that was supported by the framework 'out of the box'.
the team here at CGKineo have forked and modified the Grunt process so that it can handle this, you can find the modified version together with documentation here: https://github.com/cgkineo/adapt-grunt
This isn't something we've formally released in any way yet so, while you're welcome to use it, it's not officially supported by the Adapt Community.
I think Chris Jones/Sponge have also done something similar but I don't know where that can be found, sorry.
FYI if you're talking about creating a 'multi-SCO package', this will help with creating all the SCOs from a single codebase - but the actual act of packaging them together into one you'll have to do manually.