IPv6, prefixlen

This story started when I discussed with our openSUSE member Marek Stopka and he told me that he is running IPv6 network but because of really bad support in YaST2 he needs to configure that manually.
Oh, what a shame! So we made a deal that he'll test my patches and I'll try to implement initial support.
So now we have initial support for IPv6 in YaST. Initial means that you're able to configure "primary" address IPv6 type. Nothing more, nothing less.
Because of this I add new parameter to configure prefixlen (in v6 there is no netmask as we know from v4). In UI you can configure prefix with a little trick - instead of 255.255.255.0 you can write "/24".

Ok, example of CLI:

linux-1pi7:~ # yast lan list
0       79c970 [PCnet32 LANCE], Not configured

1       79c970 [PCnet32 LANCE], Not configured

linux-1pi7:~ # yast lan edit id=0 ip=2001:15c0:668e::5 prefix=48
Ethernet Network Card
MAC : 08:00:27:80:b5:07
Device Name: eth1
Started automatically at boot
IP address: 2001:15c0:668e::5/48


linux-1pi7:~ # yast lan list
0       Ethernet Network Card, 2001:15c0:668e::5

1       79c970 [PCnet32 LANCE], Not configured

linux-1pi7:~ #

And some screenshots from ncurses UI:






Of course there's still much work to implement full support, routing, network services support, test all possible cases, AutoYaST, etc.
Implemented in yast2-network-2.17.1