Increase MySQL version

The old one is no longer available. And the URL is dead, anyway.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
git clean requires -n or -f

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Make sure that the javabridge is built

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