add script for auto-generating links in CHANGELOG
add script for auto-generating links in CHANGELOG

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naturalatlas/mapnik,lightmare/mapnik,mapnik/mapnik,mapnik/mapnik,tomhughes/mapnik,naturalatlas/mapnik,mapnik/mapnik,naturalatlas/mapnik,mapnik/mapnik,lightmare/mapnik,tomhughes/mapnik,naturalatlas/mapnik,lightmare/mapnik,lightmare/mapnik,tomhughes/mapnik,tomhughes/mapnik