RFR: JDK-8196618: Create API to list supported values for javac --release option

[Jan Lahoda]

Hi,

This enhancement requests that test need to be able to query the list of 
supported --release options. This is possible using the 
JDKPlatformProvider, so I updated two tests where this seemed useful. 
But while doing this, it turned out the jdeprscan was not yet fully 
updated to JDK 11 (still refers to java.se.ee and did not list 11 in the 
help text for the --release option), so I updated that as well.

Bug: https://bugs.openjdk.java.net/browse/JDK-8196618
Webrev: http://cr.openjdk.java.net/~jlahoda/8196618/webrev.00/

How does this look?

Thanks,
     Jan