Always refresh services after changes

Most configuration changes needs a refresh of a service and a restart.
While the restart should probably handled by the end user with a
subscribing service resource, calling refresh seems safe.

The refresh also seems to be necessary for changing stuff like timezones
and environment variables as stated in
http://docs.oracle.com/cd/E23824_01/html/E24456/glmwl.html#gllkr
Merge pull request #6 from stschulte/service_refresh

Always refresh services after changes