Dont ship default v2_key on cfme appliance

manageiq appliance:

No change.  Default `v2_key` to make out of box experience as smooth as possible.

cfme appliance:

Don't ship with a default `v2_key`. Focus on flexibility over customer experience.

This is intended to help address https://bugzilla.redhat.com/show_bug.cgi?id=1132893

/cc @chessbyte @jrafanie @Fryguy