on list_locations return default location, rather than fail
allow spaces in Rackspace server names

remove space-stripping code for Rackspace, since it affects only
first gen servers. Next gen allow the spacing in server names
fill in the backend in  machine create wizzard, if there exist only 1 backend. Also for location/key
Merge branch 'billing' of https://github.com/mistio/mist.io into billing
ask for user details in a less aggressive way