Need to extend jnlp parser/launchdesc/etc. to support FX 2.0:
   - validate if FX is present
   - trigger FX install if needed
   - provide main class, preloader class & other parameters

Syntax will be defined as part of 6990874.

This is also related to 7000588 but 7000588 has emphasis on how to use this info to ensure FX env is set.