Update mailmap
Update mailmap

Update mailmap and keep this file
in alphabetical order.

Change-Id: I657b83202de3fdf6f4624567dfa8a53ca3ea5b39

gotostack/neutron-lbaas,gandelman-a/neutron-lbaas,dougwig/x-neutron-lbaas,gandelman-a/neutron-lbaas,gotostack/neutron-lbaas,citrix-openstack-build/neutron-lbaas,gotostack/neutron-lbaas,gandelman-a/neutron-lbaas