[10] Review request: 8177985 Use Marlin renderer as the default FX rasterizer

[Jim Graham]

JBS: https://bugs.openjdk.java.net/browse/JDK-8177985
webrev: http://cr.openjdk.java.net/~flar/JDK-8177985/webrev.00/

The only way to get one of the old Pisces rasterizers now is to manually disable Marlin (or use the new order option as 
follows).

This fix also introduces a similar pattern for rasterizer selection that we use for pipeline selection:

-Dprism.rasterizerorder=listof(
     marlin|marlinfloat|marlindouble|
     pisces|javapisces|nativepisces|
     *)
(unknown values are ignored for future/backwards-proofing)

Suggestions for naming of the new rasterizer identifiers and the "public name" strings are welcome...

			...jim