Here's a community-wiki version of your answer if you'd like to accept it as the answer.

This answers my question:

http://www.kernel.org/pub/software/scm/git-core/docs/howto/using-merge-subtree.html

Here's a community-wiki version of your answer if you'd like to accept it as the answer.

This answers my question:

http://www.kernel.org/pub/software/scm/git/docs/howto/using-merge-subtree.html