Updated to use latest logback for itest.

git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@1587611 13f79535-47bb-0310-9956-ffa450edef68
FELIX-4486: fix possible thread leakage:

- replaced the ExplodingOutputtingInputStream with a much simpler 
  ContentCopyingJarInputStream that levarages the JarInputStream to copy
  entries while they are read;
- added some test cases to verify the new implementation.



git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@1587613 13f79535-47bb-0310-9956-ffa450edef68