add Ruhrgebiet

added links to Rheinland and Stuttgart

Closes #217

The ath9k update causes frequent panics, to revert it for now.

This reverts commit a889b127.

Update hardware.rst

More information on how to get correct image file naming.

Adding support for TL-WA850RE

basic wifi meshing with neighbouring nodes
tested, with TL-WA750RE
 
client WLAN (if applicable)
works
 
client lan on LAN ports (if applicable)
n/a - only 1x Ethernet 

mesh-vpn on WAN port
works 

mesh-on-wan
Not tested

re-entering configmode by pressing the button for >3 seconds
works. 

entering failsafe mode
works 

whether the MAC address seen by Gluon is the one printed on the device
yes
 
Und folgende Kommandos:
tail /lib/gluon/core/sysconfig/*
brctl show
lua -e "print(require('platform_info').get_image_name())"

root@XXX:~# tail /lib/gluon/core/sysconfig/*
==> /lib/gluon/core/sysconfig/primary_mac <==
(macwieaufgerätaufgedruckt)
==> /lib/gluon/core/sysconfig/setup_ifname <==
eth0
==> /lib/gluon/core/sysconfig/wan_ifname <==
eth0


root@XXX:~# brctl show
bridge name	bridge id		STP enabled	interfaces
br-wan		7fff.(primarymac)	no		eth0
br-client		7fff.(primarymac)	no		bat0
							wlan0-1


root@XXXX:~# lua -e "print(require('platform_info').get_image_name())"
tp-link-tl-wa850re-v1

Adding support for TL-WA750RE

Conflicts:
	docs/user/getting_started.rst