hg: jigsaw/jake: Use VERSION_SHORT again, now that jtreg has been updated

[jonathan . gibbons]

Changeset: 1c8c3c9e2494
Author:    jjg
Date:      2015-12-03 14:01 -0800
URL:       http://hg.openjdk.java.net/jigsaw/jake/rev/1c8c3c9e2494

Use VERSION_SHORT again, now that jtreg has been updated

! make/CreateJmods.gmk