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PR contains modifications to build the SMuFL Browser on Windows. 

1) xmlsh only needed path adjustments, I handled this in a `<condition>` in the build file (alternatively, we could set the full path in the properties file, do you think this would be better?)
2) I substituted the fontforge - mogrify image processing pipeline with a small java program based on a class for the glyphPicker plugin, because I couldn't get fontforge and mogrify to work with Bravura. Fontforge would crash without an error message when called to output eps files; outputting svg files works, but these svgs result in full-black images when converted with mogrify. Inkscape can handle the svgs, but doesn't seem to allow batch processing - running inkscape anew for each svg takes > 30min on my PC. 
Could you check if the java solution works on your system and do you think this might be a cross-platform option?