print-tipc: variable 'prev_node' is reassigned the same value
NDOize ATM, MPTCP, NTP, VTP & Whiteboard decoders
NDOize 7 more small decoders

This change converts DVMRP, DLT_ENC, EGP, GeoNet, NetFlow, SLIP and TFTP
decoders.
NDOize VRRP decoder
remove duplicate prototypes from netdissect.h
use ND_PRINT in print-esp.c
print-llc: add a missing break
print-babel: don't parse two times the same field.
update the ITA URL in README
Makefile.in: add strdup.o target ; remove getaddrinfo.o nonexistent target
DNS: fix a typo
NDOize BOOTP, DHCPv6, DNS, PIM and sFlow decoders

Also add/remove tabs in a few involved functions to justify indentation.
OpenFlow: add IANA-allocated TCP port

OF specifications 1.0.2 and 1.3.3 use a different port number. That
said, the old port is still likely to be seen in the wild after 4 years
of deployment. Let tcpdump recognize both for a while.
print-sunrpc: fix old-style function definition
finalize some previous NDO conversions

Eliminate a number of fputs(), putchar() and fflush() uses. Justify
preprocessor directives. Don't typecast ND_PRINT() to void and fix some
indentation.
NDOize AODV, IPv4 and SCTP decoders
parsenfsfh: fix old-style function definitions
remove an unused declaration from netdissect.h
make use of ND_DEFAULTPRINT()
NDOize BGP decoder