[EUCA-4254] Remove backport-util-concurrent usage
Quick update on this: I have a build in Fedora where this is being tested. Unfortunately, changing this in Eucalyptus alone does not buy us much, because the official mule build still requires this library (which means our product will still have to ship it). Still, I'll see if we can get this merged into a future release.
Thanks again for the patch.
Merged into testing