Preparing Gluon for Babel

[tcatm]

Basically, fix all implicit deps on batman-adv in various packages:

• gluon-radvd refers to bat0 here https://github.com/freifunk-gluon/gluon/blob/master/package/gluon-radvd/files/lib/gluon/ebtables/300-radv-input-output
• gluon-radvd must run on local-node instead of br-client (for the next-node-mac to become the gateway)
• uradvd --default-lifetime setzen (z.B. auf 900)

the following packages also do contain references to "bat"

• gluon-mesh-vpn-fastd (refactoring necessary, split into vpn-part, batman-part, babel-part)
• gluon-respondd (allow respondd to realize that interfaces changed like uradvd, remove hotplug script)
• gluon-status-page
• gluon-status-page-api
• gluon-mesh-vpn should add the mesh-vpn interface to /lib/gluon/core/mesh_interfaces, one interface per line.

[tcatm]

• network.local_node_route6 must be removed

[christf]

most of this is done in #934
the following is still open

• statuspage / statuspage-api
• gluon-respondd

[christf]

gluon- respondd is mesh-protocol agnostic with #946

[christf]

I do not think we need respondd to notice if interfaces change for a new mesh protocol. Sure, it should be done but is not necessary for babel.

[christf]

the babel-speciic parts have been implemented. Creating a new issue for respondd