nova evacuate is an admin command

nova evacuate is an admin command and thus should be described in
the Admin User Guide and not in the End User Guide.

Change-Id: Ib5b8c72f87a17553468895a9b390c228abb4dd4b
Closes-Bug: #1222736
Clarifies description of SAN style of storage through expansion of TLAs

this change addresses the issue in Master, but Grizzly must still be
addressed.

closes-bug:#1227867

Change-Id: Iafc6e54725beaac2126c5c42fa1a67472464be87
Merge "Clarifies description of SAN style of storage through expansion of TLAs"
Merge "nova evacuate is an admin command"