Also add documentation about config mode settings.

We must ensure that each node becomes IGMP/MLD querier for its local
clients; having only a single querier for the whole mesh is generally
unreliable, leading to frequent "IGMP/MLD querier appeared/disappeared"
messages from batman-adv and unreliable snooping.

In smaller meshes it might be interesting only segment querier domains, but
allow membership reports to pass through the mesh, in order to support
snooping switches outside the mesh without special configuration. A
site.conf switch is provided to control this behaviour.

Fixes #1320

* change type of next_node.name
* create domain entry for each entry and add to dnsmasq configuration

[Matthias Schiffer: reword documentation]

[Matthias Schiffer: slightly clean up code]

This is currently only implemented in the gluon-mesh-vpn-fastd
package.

Advertising the public key may be deemed problematic when
your threat-model involves protecting the nodes privacy
from tunnel traffic correlation by onlink observers.

It can be enabled by setting site.mesh_vpn.fastd.pubkey_privacy
to `false`.

This package drops all incoming router advertisements except for the
default router with the best metric according to B.A.T.M.A.N. advanced.

Note that advertisements originating from the node itself (for example
via gluon-radvd) are not affected.

[Matthias Schiffer: rebase]

The 'auto' attribute still allows enabling the interface using ifup, which
is not intended when wired mesh is disabled.

fixes an error and removes the focus on ath10k

defaults to 11s, allowing to build devices without IBSS-support

obsoletes GLUON_ATH10K_MESH

Without -v, hexdump would sometimes replace duplicate bytes with "*" and
a newline.

The group was renamed during the development of Gluon v2017.1, adjust the
documentation accordingly.

Adding the fact that GLUON_RELEASE is needed with 'make manifest'
if it is used with 'make'.

This fact was mentioned in the v2017.1 release notes but is not (clearly)
mentioned inside other parts of the documentation.

Signed-off-by: Chrissi^ <chris@tinyhost.de>

[Matthias Schiffer: minor rewording]

Adding hints that the next_node name should contain a dot to avoid (mobile) browsers interpreting "nextnode" as searchphrase. Also setting it to an fqdn helps when clients use static dns servers.