pushed the winstone dependency to the <dependencies> so that we can see the source code during debugging

occasional test failures. See JETTY-1149.

Recording the earlier changes and the integration of the new
executable-war.

JENKINS-8658 depend on latest executable-war. This is where the fix should be. Note: of course one should release that dependency into a stable version

Since we've just changed the group ID and break everyone who depend on
the old artifact GAV, might as well rename artifact IDs as well.
(Otherwise we'd break people twice.)