Make sure that bare plugins can be loaded

TODO

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Import all TestUtils' methods statically

That is much nicer to read.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Add a unit test to verify that bare .class plugins are run correctly

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Merge branch 'bare-plugins'

This topic branch fixes the problem where bare .class plugins were no
longer picked up by a legacy environment when noPluginClassLoader() was
called (which is now the default for ImageJ2/Fiji).

The problem was reported by lots of people and fixed during the opening
game of the world cup 2014. Brazil won.

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