Upgrade to 2.4.0 version of GWT and GWT Maven plugin.
Upgrade to 2.4.0 version of GWT and GWT Maven plugin.

The latter now includes my -XdisableRunAsync patch, so we no longer need my
patched version of the 2.3.0 GWT Maven plugin.

Just-/playn,Just-/playn,KoriSamui/PlayN,Just-/playn,KoriSamui/PlayN,KoriSamui/PlayN,Just-/playn,Just-/playn,KoriSamui/PlayN