v2.2.1

• Switch basic elevation coverage to community WMS server https://wms.worldwind.earth/elev layers SRTM+GEBCO.
• Fix incorrect Placemark transformation on tilt and pitch.
• Add Gradle configuration files to build project instead of Ant.
• Replace library dependencies from local files to remote Maven Central dependencies.
• Fix GeoTiff writer issue.
• Fix some MilStd tactical symbols rendering.
• Improve WCS error handling.
• Fix decimal separator in CoordTest.
• Fix MGRS calculation issues.
• Fix Mapbox tiling problems.
• Fix null globe in fly to orbit.
• Update GDAL dependencies and improve its usage.
• Optimize Google Mercator tiled image layers logic.
• Fix MacOS pixel scale.
• Add surface text rotation.