X70 is the project number for the current Renault Master.
Source: http://www.planeterenault.com/forum/noms-de-code-renault-projets-variantes-moteurs-t6022.html
Probably with more specific letters instead of X depending on the body style, e.g. F for the van, J for passengers version, U for chassis-cab, etc. but I am not sure of these.
I do not know what naming use Opel/Vauxhall/Nissan