message: Don't use visionaray exports in lib-common
diff: #ifndef VSNRAY_COMMON_GL_DEBUG_CALLBACK_H
  #define VSNRAY_COMMON_GL_DEBUG_CALLBACK_H 1
  -#include <visionaray/export.h>
  -
  namespace visionaray
  {
  namespace gl
  @@ -81,7 +79,7 @@ class debug_callback
  {
  public:
  - VSNRAY_EXPORT bool activate(debug_params params = debug_params());
  + bool activate(debug_params params = debug_params());
  private:
  