MiniMaven: point out unknown options
MiniMaven: point out unknown options

Rather letting the user guess which of the command-line options could
not be understood, let's try to be nice and report the unknown option.

Signed-off-by: Johannes Schindelin <53fb8db7833fca1e1746dd8592f61048d350f64c@gmx.de>

TehSAUCE/imagej,TehSAUCE/imagej,biovoxxel/imagej,biovoxxel/imagej,biovoxxel/imagej,TehSAUCE/imagej