reschedule interfaces in netlink
removing pure parser and locations

Trying to make this build on Ubuntu 14.04
remove ifacedef from grammar

Each interface will be defined in its own file in radvd-2
reverting some of the interface api

This wasn't well thought out or designed.  Undo this for now.
loop over the config.d directory and read each file
remove tuntap.h
conf_file->con_path
cleanup gram.y multi-config reading code
Prepend each config file error with fname

There is now one config file per interface and we need to know
what files are generating the warnings/errors.  This change adds
the filename and line number to the errors and warnings.

For this to properly work, bison locations needs to be enabled.
add flex/bison locations
pass null to ppoll timeout when there's nothing to do
no more need to reset signal

using sigaction now, dont reset the signals in the signal handlers
fill in find_iface_by_time

This loops over the linked list of interfaces looking for the lest time
value and returns the pointer to that interface.
interface.c: fill in find_iface_by_index

Loop over the interface linked list looking for the interface with index
gram.y: override incorrect setting of AdvDNSSLLifetime

If the setting is wrong, and we know why, override it instead of die.
radvd.c: protect access to timespec ts with scope

This creates a static stack variable, but protects its use.
update trivial.sh test to use config path

This updates the test to work with the new scheme of using an radvd.d
directory which stores interface configs in seperate files in radvd.d.
add contrib/unset_addrs.sh

this will remove all global ipv6 addrs from an interface
add del addr handling in netlink
add stubbed out code to disable autoconf on an iface