Revert "second step of renaming activitystreams_unofficial submodule"

This reverts commit d3f2a6b76d93474c34c41d7f373d9d098f358e4b.
Revert "rename activitystreams submodule dir to activitystreams_unofficial"

This reverts commit 6c7832d3c41dd01a58ba3b0259b64ae65112eeaf.
add tweepy submodule symlink