dnsmasq: security bump to version 2.78

dnsmasq: security bump to version 2.78

Supported Lua version is now 5.2.

Add licenses hash.

Fixes a number of security issues:

CVE-2017-13704 - Crash when DNS query exceeded 512 bytes (a regression
in 2.77, so technically not fixed by this bump)

CVE-2017-14491 - Heap overflow in DNS code

CVE-2017-14492 - Heap overflow in IPv6 router advertisement code

CVE-2017-14493 - Stack overflow in DHCPv6 code

CVE-2017-14494 - Information leak in DHCPv6

CVE-2017-14496 - Invalid boundary checks allows a malicious DNS queries
to trigger DoS

CVE-2017-14495 - Out-of-memory Dos vulnerability

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>