Fix FELIX-4106
Defensive service registration and update

git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@1489947 13f79535-47bb-0310-9956-ffa450edef68
Fix FELIX-4105	
Factories not disposed when their bundle is leaving

git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@1489948 13f79535-47bb-0310-9956-ffa450edef68