Network test server IPv6 upgrade

Upgrade the services on the test server to accept IPv6 connections

The test server requires an upgrade before we can do dual stack testing against it.

• The danted* SOCKS proxy doesn't support IPv6 (SS5** does, but isn't available as a package, only a source tarball)
• The squid3 HTTP proxy needs a package update and configuration change
• Apache needs a configuration change Vsftpd needs a configuration change, possibly a package update
• The frox FTP proxy doesn't support IPv6 (I have not looked for an alternative yet.)
• FTP is not network layer transparent

The CI environment requires IPv6 connectivity between test machines and test server

• Link local (autoconfigured) addresses are not good because scoping is required in the hosts file
• Ideally an internal DNS would return both the v4 and v6 addresses (A and AAAA records for qt-test-server)
• Before deployment of hosts files/DNS AAAA record, need to check the existing tests still work

One way to work on this could be to have a qt-test-server-v2.qt-test-net which has the new configuration. A feature branch in qtbase would test against this configuration.

There would need to be a puppet configuration option, so a test server can be configured as an old v4 server (still needed to test patch releases of old Qt versions), or a new v4+v6 server.
Need the instructions in the README for setting up both types of server.

(initial development can be done by locally cloning a test server VM and replacing services on it - however it would need to move into the puppet configuration at some point)