Merge branch 'master' into gh

linux/README: details on configure usage

patches to vtnet and em drivers

v1000/socket support available

mem: better debugging for netmap_mem_{get,put}

Merge branch 'next' into master

adapt to the counter interface on FreeBSD head (commented out, anyways)

remove stale comment

remove trailing whitespace

merge with master up to 2014-04-03