[B.A.T.M.A.N.] reorganized kernel interface patches (version 2)

Hi,

I merged the feedback given so far into the patchset and post them again to offer you the chance of generating even more feedback. :-)

Changes since version1: * the known issue from version1 turned out to be a bug in the used kernel * batctl sysfs path has been changed to /sys/class/net/ since older kernels don't provide the "virtual" subdirectory * the year of the copyright notice was corrected * In case the erroneous of input contains a newline it will not be printed to avoid printing 2 subsequent newlines * the function calls which used global variables before now receive the bat_priv struct as an argument * added _GNU_SOURCE to bat-hosts.c to avoid compile warning * batctl gets bonding mode support

Cheers, Marek