The batadv debugfs requires large memory blocks to write the text debug
tables. This is inefficient for large tables like the global translation
table or the originators table.

The memory requirement can be reduced by using netlink. It copies smaller
packets in a binary format to the userspace program. The respondd module of
gluon-mesh-batman-adv-core can therefore parse larger originator tables
without causing an OOM on systems which are tight on memory.

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

Fixes #834

[Matthias Schiffer:
  - improve commit message
  - add pidof check
  - also call `wifi down`
]

Should be redundant after 0bd0df6f

gluon-announced and gluon-announce are merged to gluon-respondd.

This package provides br-client and sets up a wireless AP interface for
clients.

gluon-radio-config contained only a single file. The code has been adjusted
to allow creating a Gluon configuration without WLAN support by removing
the wifi24 and wifi5 sections from site.conf.

Split basic radio configuration from gluon-mesh-batman-adv as this will
be required for virtually any wireless mesh protocol.

This package takes care of setting:

  - wireless channel,
  - htmode and
  - regulatory domain

gluon-mesh-batman-adv-core depends on this package.

This adds a new announce.d datum "neighbours" (alfred 160) containing
information about mesh neighbours. It's intended to be an replacement
for batadv-vis.

In addition to the data already provided by batadv-vis it'll also
provide information about direct wifi neighbours.

Unlike batadv-vis, no data about clients is transmitted.

Sample data:

    {
      "wifi": {
        "90:f6:52:82:06:02": {
          "neighbours": {
            "f8:d1:11:2c:a7:d2": {
              "noise": -95,
              "inactive": 0,
              "signal": 0
            },
            "96:f6:52:ff:cd:6f": {
              "noise": -95,
              "inactive": 0,
              "signal": -37
            }
          }
        }
      },
      "batadv": {
        "90:f6:52:82:06:02": {
          "neighbours": {
            "96:f6:52:ff:cd:6f": {
              "lastseen": 2.8500000000000001,
              "tq": 177
            }
          }
        },
        "90:f6:52:82:06:03": {
          "neighbours": {
            "f8:d1:11:2c:a7:d3": {
              "lastseen": 2.3500000000000001,
              "tq": 206
            }
          }
        }
      },
      "node_id": "90f652820602"
    }