Create package directory if it doesn't exist
Create package directory if it doesn't exist

Tried installing this on the alpha0.5 branch and the package directory
did not exist yet, so copying the db files failed.


Former-commit-id: 596fb4c6e7e8294415e6c81ec1476d26f209862b
gsarma/PyOpenWorm,gsarma/PyOpenWorm,hnunner/PyOpenWorm,kaustubhcs/PyOpenWorm,travs/PyOpenWorm,openworm/PyOpenWorm,openworm/PyOpenWorm