HEADS-UP: Dropping support for some older Linux distros in JDK 9

[Kevin Rushforth]

As a heads-up, we are changing our production build environment for 
JavaFX to Oracle Linux 7 with a dependency on GLIBC_2.14. This means 
that JavaFX applications will stop running on some older Linux distros, 
specifically Oracle Linux 6. I filed an issue in JBS [1] to track this 
change.

The reason for this is to support the latest version of GStreamer [2] 
which requires a newer version of GLib than what is available on OL 6.

-- Kevin

[1] https://bugs.openjdk.java.net/browse/JDK-8133596
[2] http://openjdk.java.net/jeps/257