fixup! Fall back to the remote updater if ImageJ cannot be started
Fall back to remote Javascript to fall back to updater

In case Javascript is not available, let's get js.jar remotely, too

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

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
fixup! Fall back to remote Javascript to fall back to updater
wip