Adding Karaf features for L2switch

Also added a local karaf distributions.

cd distribution/karaf/target/assembly/bin
./karaf

And it will come up running l2switch and restconf.

Point mininet at it, pingall, and look at the host tracking
in topology:

GET http://localhost:8181/restconf/operational/network-topology:network-topology/

Had to force maven bundle plugin to 2.4.0 as 2.5.0 is incompatible
with karaf

Change-Id: I0ff09b6d330d3fc7e741cfdc8d652637fdea8ff3
Signed-off-by: Amit Mandke <ammandke@cisco.com>
Signed-off-by: Ed Warnicke <eaw@cisco.com>