updated debian packaging; dnssd & mdp plugins are packaged into olsrd-commotion-plugins

to test, build on OpenWRT and make sure olsrd, olsrd-dnssd, and olrsd-mdp still work.

Here's a config block for olsrd-mdp: 

    LoadPlugin "olsrd_mdp.so.0.1"
    {
            PlParam "sid" "A6D29C35D0409F176B22AEF2FAC447572540F39D8AEB8C48C107F9A11D224B06"
            PlParam "servalpath" "/etc/commotion/keys.d/mdp"
    }

We should also consider whether we want this to be merged into the release-0.6.5.4 branch, or if we should make our own commotion branch. Thoughts, @jheretic ?