Bump to current parent version

We require a new scijava-common version for the next steps...

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
React to the ContextDisposingEvent by closing the script editor

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
React to the ContextDisposingEvent by closing the updater GUI

For backwards-compatibility with Fiji_Updater.jar, we cannot just
add the EventHandler in the UpdaterFrame class: the event was *just*
introduced into scijava-common and will be unavailable in the near
future whenever there is some version skew.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>