Merge branch 'release-0.46.0' into develop
Updated news feed xml source
Refactoring and cleanup
Refactoring and cleanup
Multiple changes

- Added detection for KHR_debug to the build system.
- Updated the oglplus library sources.
Added checks if certain enum values are available
Removed HardwiredProgram and QuickProgram
Refctoring and cleanup

- Split the compile-time configuration options into separate files.
Refactoring and cleanup
Added the Group<> template
Re-added the QuickProgram class
Minor update in example exception handling
Added a new example
Updates in compile-time compiler-related config

- Replaced the deprecated BOOST_NO_* macros with BOOST_NO_CXX11_*.
Fixed compiler configuration
Added a new example
Multiple changes

- Moved some of the image-related functions to the implement/ header.
- Added new vector typedefs.
- Added new operators to Vector.
- Updated some examples.
Added the voronoi/worley cell image generators
Added the VoronoiCells image generator
Added the WorleyCells image generator