New in SIM Voleon v2.1.0 (2019-12-26):
* new:
  - Kongsberg Oil & Gas Technologies AS ended SimVoleon as a commercial product
    and re-licensed it under the BSD 3-clause license as a service to the
    user community.
  - The build system has been migrated from GNU Autotools to CMake
  - Support for BitBucket and AppVeyor as continuous integration service providers

* bugfixes:

New in SIM Voleon v2.0.1:

* bugfixes
  - mixing 2D-textures and 3D-textures with the same palette would
    sometimes break, causing rendering artifacts
  - fixed a major resource leak for OpenGL textures
  - obscure bug in optimalization feature for tracking "open" areas fixed
  - rendering code is now multithread-safe

New in SIM Voleon v2.0.0:

* new features
  - SoObliqueSlice node
  - SoVolumeFaceSet, SoVolumeIndexedFaceSet, SoVolumeTriangleStripSet
    and SoVolumeIndexedTriangleStripSet nodes
  - SoVolumeSkin node

* bugfixes
  - data was previously rendered flipped on the Y axis, now fixed --
    note that this is a major semantic change which needs client code
    to be updated, see the RELNOTES document
  - 3D-texture based rendering for SoVolumeRender nodes now works
    correctly for any preceding scene graph transformations
  - many minor bugfixes
