Add support for TP-Link TL-WR710N v2

Tested-by: @kokel

The nodeinfo/network/addresses announcement included deprecated and
tentative addresses, which it clearly shouldn't as the host doesn't want
to be contacted on those addresses. They are now filtered out.

TP-Link TL-WA701ND v2: remove BROKEN

hostapd would switch the primary and secondary channel on 5GHz networks in
certain circumstances, completely breaking the adhoc interfaces of the WLAN
adapter (they would lose their configuration).

As a temporary fix, disable this channel switch function.

While the images are the same that are used for the Bullet M, adding these
copies will help users choose the correct image for their device.

These are identical to the TL-WR941ND (and identify as TL-WR941ND
internally).

doc: remove "probability" from site doc (was removed in v2014.3)

see: http://gluon.readthedocs.org/en/latest/releases/v2014.3.html



Signed-off-by: Alexander Dahl <alex@netz39.de>

The file targets/$GLUON_TARGET/config becomes optional, as many targets
only used it to set the board and subtarget.

Also fix targets without subtarget.

This default to n now by default

These packages are included by OpenWrt by default on this target and don't
need to be specified manually.

gluon-neighbour-info: Support sub-second timeout

This was broken due to the switch to Chaos Calmer.

This fixes MAC address conflicts on devices which use the eth0 as primary
address.

This should fix the signal strength indicators on the TP-Link CPE210/510.

These targets don't have a WLAN adapter by default, so it doesn't make
sense to default to the phy0 address.

Original patch by @MPW1412

Fixes build for brcm2708 targets

It seems to have been deleted accidentially.

Do not use error() in gluon-neighbour-info

error() is a glibc specific function and should not be used in
code meant to be portable.