Setting the FreeType LCD filter

[John Neffenger]

I think I found the cause of the text rendering problem I have always 
seen in JavaFX applications on Linux:

Reduce color fringes in FreeType subpixel rendering
https://github.com/javafxports/openjdk-jfx/issues/229

I'm finally seeing the fonts as they were intended! I used the Oracle 
bug report outline as a template for the GitHub issue to make it easy to 
copy to the Java Bug Database. Do I need a Java Bug ID before I submit a 
pull request?

Thanks,
John

P.S.: For background information, there is a great demonstration of LCD 
filtering algorithms by Felipe Heidrich at 1:02:47 into the video 
"JavaFX Text Rendering" <https://youtu.be/LCrCni6EVek?t=1h2m47s>. The 
link takes you directly to the two-minute segment showing the text 
rendered by FreeType, first with no filter, and then with its various 
filter options. (Note: the audio is a bit loud.)