Rails 3 substruct documentation

Hello all,

Does anyone know where I can find documentation for the Rails 3 branch
of Substruct (shopping cart)

I found this branch but the documentation looks to be the same as the
rails 2.

http://github.com/rubyjedi/substruct

I still tried to follow this just to see, but when I get to $ rake
gems:build I get the 'Don't know how to build tasks 'gem:build'

Then when I do the $ rake substruct:db:bootstrap I get:
"Mysql2::Error: Table 'quilting_development.content_nodes' doesn't
exist: SELECT `content_nodes`.* FROM `content_nodes`"

Also the substruct for rails 2 was a whole application while the rails
branch I downloaded only what went in the vender/plugins file and did
not include the Gems.

Any thoughts or help in finding the documentation would be appreciated.

Thank you in advance