Bug 2002: Classpath error when loading neutron northbound api

Adding restconf to the opendaylight-karaf distribution
This is a back-port merge request from Lithium to Helium for
gerrit https://git.opendaylight.org/gerrit/#/c/11862/

Change-Id: I309215ac8fb84663d5169596ccc565a94d3eb345
Signed-off-by: Colin Dixon <colin@colindixon.com>
Signed-off-by: Flavio Fernandes <ffernand@redhat.com>