gluon-mesh-babel: babel-respond: stop relying on mac addresses and instead obtain ll-address from nic

gluon-wan is a sudo-like exec wrapper that switches the process group to
gluon-mesh-vpn, making it use the WAN dnsmasq rather than resolving over
the mesh.

Note that this only affects DNS at the moment. Processes running under
gluon-wan will still use the regular mesh IPv6 routing table, and not the
WAN routing table. This is not a problem for IPv4, as there is only one
IPv4 routing table.

Fixes #1575

Rename to respondd.c / respondd.so, gluon.mk expects these names. This way
we can remove the install code. The installed filename is changed to
gluon-mesh-babel.so, bringing it in line with out common naming scheme.

The redirect and dnat target are needed for gluon-alt-esc-client to
forward frames to the selected, alternative gateways.

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

This adds support for the TP-Link TL-WR902Ac v1 travel router.

The device is marked as broken due to 64MB which might be insufficient
in certain environments.

Do not require this setting in site.conf.

Before 7827f896, mandatory hostname field in config mode was
pre-filled with the default hostname.

This commit adds the config_mode.hostname.prefill option for
controlling the default value.

this activates the package by default when using the batman feature
while still allowing to explicitly remove it like this:

GLUON_SITE_PACKAGES := \
  -gluon-ebtables-limit-arp

gluon-config-mode-geo-location-osm extends the
gluon-config-mode-geo-location with a location picker based on
OpenStreetMaps.

Based-on-patch-by: Jan-Tarek Butt <tarek@ring0.de>

The new code is shorter and uses more readable variable names. It does not
depend on specifically named input fields anymore (allowing to use multiple
maps on the same page), and only uses well-defined interfaces to trigger
revalidation of input fields.

The Map model class allows to add OSM maps to gluon-web forms.

Can be used for inserting Lua values into inline JS code.

At least the ifindex and the flags fields can be larger than 0xff.

Fixes #1523

Let gluon-respondd expose "MemAvailable" from /proc/meminfo to allow for
a more realistic memory-usage estimation.

Information on MemAvailable can be found here:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/
commit/?id=34e431b0ae398fc54ea69ff85ec700722c9da773

As already done with other config mode texts, the altitude field now has
default texts that are used when they are not set in the site i18n files.
The altitude-help text has been removed from site i18n; instead, the
geo-location-help text now overrides the whole section description
including the part that mentions the altitude.

Do not show by default, delete old altitude value when a form without
altitude shown is saved.

Fixes #1493

Revert "gluon-core: make sure dns traffic leaves the correct interface when there is ipv6 wan uplink"

This reverts commit b3d70111.

with this change, DNS in batman-adv based networks is broken.
although the revert breaks babel based networks, this is not as big of a problem.

Signed-off-by: Jan-Tarek Butt <tarek@ring0.de>

Signed-off-by: Felix Kaechele <felix@kaechele.ca>