Removed *.ini configuration steps from Nova compute section

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

Change-Id: I2c2e75f1855752a68fec2686a9ff639bef97eacd
Closes-Bug: #1287900
Merge "Removed *.ini configuration steps from Nova compute section"