GitLab

 - not used function removed
 - DHCP6_HOOK_PACKET_RCVD_SKIP message typo fixed

- callouts called using HooksManager::callCallouts
- removed Dhcp6Srv::getServerHooks() and getHooksManager() declarations.
- updated sendPacket comment (reception->transmission)
- documented getCalloutHandle()
- indentation fixed for getSubnets6()

in D2 unit test.

Don't warn about static cast of function pointer print.

To silence cppcheck.

This change added in response to a "make distcheck" failute on one
of the build systems.

Only OSX uses ".dylib" as a suffix for shared libraries.  Adjust
configure.ac so that the operating system can be better determined,
and ensure the hooks tests use the correct suffic for the test shared
libraries.

The hooks system can only load shared libraries, even if BIND 10 is
linked statically.

Absence of "libdl" on BSD systems required an addition to configure.ac
to check its presence.  Problems with converting "pointer to object"
to "pointer to void*" via reinterpret_cast on Solaris required an
extension to the Pointer_converter class.

In particular, added a doUpdate version which supports TSIG. It is also
possible to specify Transport layer protocol preferred.

This reduces the risk of someone taking a copy and being left with
a "dangling pointer" to a callout manager.