git submodule supports relative paths in submodule URLs. Use them.
-rw-r--r-- 10 .gitignore
-rw-r--r-- 685 authors
-rwxr-xr-x 3655 git-migrate-fast.sh
-rw-r--r-- 4844 rules.mako
-rw-r--r-- 4972 svn.yml