register ceilometer options at runtime

This remove pollsters option from configfile sample
due to a duplicate option registration. This will
be fixed later.

The exchange_control group in the config sample doesn't exit
in reality exchange are in DEFAULT group.

This removes usage of cfg.CONF everywhere left.

This adds all missing OPTS in sample file.

Change-Id: I48c11ee7e1aae65847958b98532b3bdb48a3ceb5

ceilometer/compute/virt/libvirt/inspector.py

@@ -39,9 +39,6 @@ OPTS = [
                     '(which is dependent on libvirt_type).'),
 ]
 
-CONF = cfg.CONF
-CONF.register_opts(OPTS)
-
 
 def retry_on_disconnect(function):
     def decorator(self, *args, **kwargs):