Fix deadlock with the EDT while opening the legacy editor

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Let Simple Neurite Tracer work with newer JUnit

The assumeNotNull() function now takes a vararg and assumes that *all*
of the passed parameters should be null...

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Merge branch 'master' of github.com:fiji/fiji