Further openSUSE instructions

dashboard: Explain database session store is configured by default

heat:
* Fix setup
* openstack-db does not handle heat yet, remove its usage

ceilometer:
* Fix setup
* Fix service startup commands

Fix passwords: it's _PASS for the keystone password and
_DBPASS for the database one.

heat and ceilometer installation has been tested but this does
not work completely yet. Need first a working network install.

Change-Id: I8007b79dd109e7e41aa45735f5044e723604faf9
Merge "Further openSUSE instructions"