* support latest kernels (3.16 - 5.2)
* coding style cleanups and refactoring
* implement multicast-to-unicast support for multiple targets
* deprecate sysfs support and make it optional
* refresh DAT entry timeouts on incoming ARP Replies
* bugs squashed:
- fix multicast tt/tvlv worker locking
- drop roam tvlv handler when unregistering mesh interface
Signed-off-by: Sven Eckelmann <sven@narfation.org>