Bug 2014: Workaround for karaf listFeatures bug

karaf FeatureService.listInstalledFeatures() sometimes
throws a ConcurrentModificationException, this workaround
retries to make sure we succeed.

Change-Id: I4e307d5daba683dfc1b44b6524ce40b3b0e59d1b
Signed-off-by: Ed Warnicke <eaw@cisco.com>
Merge "Bug 2014: Workaround for karaf listFeatures bug"