lsm-test: use ImageMagick compare tool for image comparison.
lsm-test: use ImageMagick compare tool for image comparison.

We want to tolerate some color mismatch between pixels.
compare -metric AE -fuzz 10% does that.

janmarthedal/mathml2svg,janmarthedal/mathml2svg,janmarthedal/mathml2svg,wavewave/lasem,wavewave/lasem,gjtorikian/lasem,wavewave/lasem,wavewave/lasem,janmarthedal/mathml2svg,gjtorikian/lasem,gjtorikian/lasem,gjtorikian/lasem