Increased default timeout on server create.
Increased default timeout on server create.

Increased default timeout to 1200s to match the previous wrongly
hardcoded timeout.

tdooner/knife-rackspace,philoserf/knife-rackspace,srirajan/knife-rackspace,vhl/knife-rackspace,chef/knife-rackspace,martinb3/knife-rackspace,decklin/knife-rackspace,rackspace/knife-rackspace,chef/knife-rackspace