intf_loop relies on passing the length inside the structure to make sure
interface aliases are accounted for.

When at least one of them is in the monitor mode. The fix was to define the
ARP_HRD_IEEE80211_RADIOTAP 802.11 radiotap header identifier in the
libdnet-stripped code. Network interfaces that are in this mode are used
by radiotap for 802.11 frame injection and reception. The bug was
reported by Tom Eichstaedt and Henri Doreau.
http://seclists.org/nmap-dev/2012/q2/449
http://seclists.org/nmap-dev/2012/q2/478
[Djalal Harouni, Henri Doreau]

Changed the name of sctp_chunkhdr to dnet_sctp_chunkhdr to avoid a
conflict with a struct of the same name in <netinet/sctp.h> in FreeBSD
and Linux.

Reading from /dev/arandom || /dev/urandom should never fail, but
in order to avoid a warning about an unused result, wrap the read
in a condition

- Rebuild with newer Cython (incl. setting language_level)
- Update build chain with latest autotools
- Fixes include:
  - Update mIV_IF_TYPE
  - intf_loop aliases fixes
  - Fix bug that caused Nmap to fail find any network intf
  - Fix bug with interface indexes > 255
  - Fixed conflicting struct names in BSD and Linux
  - Prio to IFF_LOOPBACK flag when setting intf type
  - A few comp warnings eliminated
  - Small test updates