ManagedObject (in core library) cannot inherit from enable_shared_from_this
ManagedObject (in core library) cannot inherit from enable_shared_from_this

- This causes an issue with creating a std::unique_ptr<> to any ospray
  object, which is currently used in our AMR code in the ISPC device. This
  is only a limitation because ospray::api::Device needs a parameter list,
  which should be separated out into its own class as devices do _not_ need
  either memory::RefCount or std::enable_shared_from_this to manage their
  lifetime.

wilsonCernWq/ospray,ospray/OSPRay,ospray/OSPRay,wilsonCernWq/ospray,ospray/OSPRay,wilsonCernWq/ospray,ospray/OSPRay