BUG-1199 : fixed incorrect parsing of Error message.

Change-Id: I6227b82a34ae0efd6d0626bc1eef5a58e89031a8
Signed-off-by: Dana Kutenicsova <dkutenic@cisco.com>
BUG-1025 : use correct YANG syntax to avoid yangtools warnings.

Change-Id: Ic47bfb0d5fddd09c62ce271e8c48b2e31893c5a8
Signed-off-by: Dana Kutenicsova <dkutenic@cisco.com>