Removed *.ini configuration steps from Nova controller section

Nova in Icehouse doesn't seem to require configuration of *.ini files,
particularly the [filter:authtoken] section. I removed these steps
from the controller section of the Nova chapter. I also moved the
'auth_uri' key to the [keystone_authtoken] section in nova.conf.

Change-Id: I7eee6faf0b2a5e5200effba345cc84c9ec259bf5
Closes-Bug: #1287897
Merge "Removed *.ini configuration steps from Nova controller section"