Custom modules for libraries which cmake doesn't have out-of-the-box
support for.

FindNVTT and FindOpenEXR are from OpenSceneGraph (OSG):

http://trac.openscenegraph.org/projects/osg/browser/OpenSceneGraph/trunk/CMakeModules

OSG is under a modified LGPL license.

FindLCMS is from KDE (kdelibs/cmake/modules/)

