This removes PKG_VERSION and PKG_RELEASE from most Makefiles, as the
value was never useful for Gluon packages; instead, PKG_VERSION is set
to 1 in gluon.mk.

It also removes two other weird definitions:

- gluon-iptables-clamp-mss-to-pmtu replicating the old PKG_VERSION logic
  from gluon-core, but without the fixed PKG_BUILD_DIR to prevent
  unnessary rebuilds
- gluon-hoodselector set GLUON_VERSION=3

With the removal of ramips-rt305x, the last user of
GLUON_SPECIALIZE_KERNEL is gone.

The new routing_algo site.conf value BATMAN_IV_LEGACY is introduced. With
these changes, the routing_algo setting becomes mandatory.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>

The batctl v2013.4 build was removed from the batman-adv-legacy package
as the current, upstream batctl releases work with batman-adv-legacy,
too.

As a replacement we need to add the upstream batctl dependency to
gluon-mesh-batman-adv-14 to have a batctl available again here.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>

Signed-off-by: Sven Eckelmann <sven@narfation.org>

For simplicity, we don't use different MTUs for compat 14 and 15 anymore,
there's no harm in using 1532 for batman-adv-legacy as well.

gluon-mesh-batman-adv should not be used without firewall to prevent forwarding
of packets from the mesh to the wan interface.

For some reason, the firewall package won't work at all without
kmod-ipt-nathelper.