Make sure that copy-jars in Fiji_Archipelago finds jai-codec

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Port Script Editor to use ImageJ2's MiniMaven, too

Somehow this change got lost before pushing the change to fake.jar.

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