Ubuntu LTS 14.04.6 available

This is mostly relevant to our 32-bit PowerPC colleagues, but along with the recent updates to Ubuntu 16 and 18 comes what will likely be the final release of Ubuntu 14.04 LTS (read the change summary). This release is primarily security-focused, mostly to deal with the APT redirect vulnerability, though there are of course other fixes. PowerPC and POWER8 users still stuck on Ubuntu 14 should strongly consider upgrading to Ubuntu 16, which still supports 32-bit PowerPC, also supports POWER8 (but not POWER9), and is still receiving fixes as Ubuntu 14.04 will reach end of life in April 2019. Meanwhile, ISO images are available.