Deal with forked repos

[ringmaster]

For example, I create a plugin Foo and add it to the directory via the hook. Someone else forks Foo, makes some changes, and commits it, pinging the directory with the same GUID.

As a first suggestion as to how to deal with this: The directory should gracefully reject pings from repos that are forks.

As a second suggestion: The directory could account for different versions by different users by creating a different term version for forked copies. The original repo could be "0.8.x-1.0" and the fork could be "0.8.x-1.0-gituser".