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

[Steve Drach]

Hi Alan,

> It would be good to add @since to Attributes#MULTI_RELEASE before this goes in.

None of the other attributes have this.   Are you suggesting I do this?

/**
 * {@code Name} object for {@code Multi-Release}
 * manifest attribute that indicates this is a multi-release JAR file.
 *
 * @since  1.9
 */
public static final Name MULTI_RELEASE = new Name("Multi-Release");