Time to drop tuncl

I just realized that 'tunctl' is not required anymore.

Now you can create tun/tap devices with 'ip':

    ip tuntap add eth0 user USER11 group GROUP11 mode tap

Proper way to print errno value.

I use this combination of bash and python to print meaning of errno value:

strerror () { python -c "import os; print os.strerror($1)"; }

There is also 'perror' program, but it is distributed with mysql only.