Moves install info from chapter in Compute guide to Install guide.

SLES and SUSE remain, however, as there's no good reason to
include those in the rhel or ubuntu guides, is there?

Fix bug 1155215

Change-Id: I5868ab45481ae13bb1e986e964f2605dcc5f6880
Merge "Moves install info from chapter in Compute guide to Install guide."