When running on Windows, Unicode feature label chars are broken

[metteo]

Caused by getting string bytes in UTF-8:

https://github.com/mapfish/mapfish-print/blob/development/core/src/main/java/org/mapfish/print/map/geotools/FeaturesParser.java#L158

even FeatureJSON expects platform specific encoding here:

https://github.com/geotools/geotools/blob/master/modules/unsupported/geojson/src/main/java/org/geotools/geojson/GeoJSONUtil.java#L93

Quick fix would mean using String.getBytes() instead of the one accepting charset and commenting that it's used on purpose.