Bug 1890: Use output from action

Pass the output from the action command back to the caller,
regardless of the status of action completion.  This allows
for failure messages to be passed through to the LCM for
storage in the action record.

Change-Id: I268c43225b71a80e54712743e61586d57952553e
Signed-off-by: Mark Beierl <mark.beierl@canonical.com>