Recover GitGraph Java source files lost in move from Blueprints.

I was looking for the source files to go with the GitGraph example and couldn't find them anywhere.  Looks like they got lost in the shuffle when the move to Tinkubator was done.  I've reclaimed them trying to preserve their Git history, but it looks like that didn't work out.  I tried reverting the commit that deleted them [5af13418e559f6b2e2b1855dc707b010b2e5cbd0](https://www.openhub.net/p/tinkerpops_blueprints/commits/149037901) then doing a branch filter and merge but that didn't get the previous commits about them.