RFR - 8132734: java.util.jar.* changes to support multi-release jar files

[Steve Drach]

>>> As to whether this is implementation vs. JAR URL spec then I assume it needs to be spec so that libraries can create URLs that will use runtime versioning when access the JAR.
>>> 
>> 
>> Yeah, i don’t think we can avoid it.
> 
> Ok.  I guess I should put the information in JarURLConnection.

Actually it’s a bit strange documenting the #runtime fragment in JarURLConnection, because none of the changes are in that class.  The changes are in the sun.net.www.protocol.jar.JarURLConnection class that is not publicly documented.