Ensure that legacy-compatible macros find the macro options

As SciJava's script service calls scripts on different threads,
we have to make extra certain that the appropriate macro options
-- if any -- are available to the ImageJ 1.x macro engine.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Add a unit test for running macros with macro options

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