docker: allow keyspace name override
docker: allow keyspace name override

rackerlabs/blueflood,rackerlabs/blueflood,izrik/blueflood,shintasmith/blueflood,rackerlabs/blueflood,shintasmith/blueflood,izrik/blueflood,izrik/blueflood,izrik/blueflood,izrik/blueflood,rackerlabs/blueflood,izrik/blueflood,shintasmith/blueflood,rackerlabs/blueflood,shintasmith/blueflood,shintasmith/blueflood,shintasmith/blueflood,rackerlabs/blueflood