Load shaders and enumerations from configuration file, rather than code.

[bkloppenborg]

At present the function

void CGLShaderList::LoadShaders()

is statically coded to load specific shaders. To add another shader, one must add code and recompile. It might be better to specify the shaders to load in a configuration file, rather than hard-coded values.

[bkloppenborg]

Duplicate of #18 and #59. Closed in #59.