Update karaf version to latest 2.3.6

Hopefully fixing:
https://issues.apache.org/jira/browse/JCLOUDS-673
https://issues.apache.org/jira/browse/JCLOUDS-674
@demobox Yeah, you have the gist of it now.  There is a long running debate about this but I doubt it will ever be resolved: https://jira.codehaus.org/browse/MNG-5146

In the mean time, I just religiously put that in every pom referring to a remote parent because I can't stand false warnings and garbage in my build output.  I will put this in the new PR when I get that all resolved.