Makefile.am: cleanup and organize
gitignore: gcov files
gitignore: libradvd-parser.c
configure.ac: add AC_PROG_RANLIB for libradvd-parser.a
configure.ac: set VERSION directly here

This is the only way to modernize and keep up with changes in autotools
going forward.
configure.ac: start using c99 already
configure.ac: show the CPPFLAGS in output

The CPPFLAGS are the C PreProcessor flags.  C++ flags are CXXFLAGS.  Don't
get them confused.
radvd.h: move abro and 6co structs here

These struct were in includes.h, but they make more sense in radvd.h
use pragma once in header files
loc.c: char * -> char const * where appropriate
log.c: include PID in logging
log.c: use c99 scope
log.c: use static where appropriate
send.c: add add_sllao function
send.c: cleanup usage of address_text[]
send.c: use c99 scope in really_send
send.c: use c99 scope (uses sock change)
send.c: make indent
send.c: inc iface->racount here
netlink.c: add RTMGRP_IPV6_IFADDR to nl_groups