Merge pull request #1865 from mortenstevens/master

Add pdns-auth security polling status for Fedora
Add pdns-auth security polling status for Debian
Merge pull request #1866 from zeha/secpoll-debian

Add pdns-auth security polling status for Debian
Throw is serial won't fit into uint32_t, fixes #1009
Renamed strtoui to pdns_strtoui, requested by @ahu
Merge pull request #1864 from cmouse/check-serial-overflow

Check serial overflow
prevent warnings on 32 bit
Allow changing the Sockaddr in ComboAddress
Reuse existing connection when possible
Merge pull request #1868 from cmouse/remotebackend-keepalive

Remotebackend keepalive support