Deployment script removes (empty) statekeys/ directory

[aaaaalbert]

6f87d75 added an (almost) empty directory where a clearinghouse's statekeys should be stored. (The dir does contain a README file, because Git won't track completely empty dirs.)

The clearinghouse deployment script removes this dir. This made sense when the existing statekeys for seattleclearinghouse.poly.edu and betaseattleclearinghouse.poly.edu were stored there, but I've moved them to separate directories since, in 350b594.

The rmtree() of statekeys/ should thus be removed from the deployment script, deploymentscripts/deploy_clearinghouse.py.