netifd: Route type support

netifd: Route type support

Patch adds route type support in netifd by means of the route parameter type.
By default the route type was unicast; the parameter adss support for local/broadcast/multicast/unicast routes which will be put into the appropriate routing table.
If route type parameter is unset the route type will be unicast as before.

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>