IECoreNuke::DeepImageReader

Allows any deep image type that is registered to cortex to be read by Nuke's native deep image reader.

It is worth noting that supported types cannot be queried using IECore::Reader::supportedExtensions() and have been hard-coded. This is because nuke requires them within a static member initialization which, as the IECore::RunTimeTyped::derivedTypes() call is static, means that because the static initialization order is unknown, a complete list of supported extensions might not be available.