Release Highlights:
- New: osgEarthImGui NodeKit - new library that encapsulates all support for built-in ImGui control panels as seen in the osgearth_imgui application
- New: Support for self-hosted Cesium Ion servers
- New: Support for Microsoft Azure Maps image layers
- Revamped CMake packaging setup for easier deployment of osgEarth-based applications
- Performance improvements: faster image mosaicing, mercator image sampling
- Updated vcpkg support