Mint DOIs

The ESAP requirements (R-8; see deliverable D5.2) tell us that “Users should be able to assign PIDs to every digital object that is part of a Research Object”).

Currently, we've not sketched out what this means. As zeroth-order implementation might be some means of assigning a DOI to the contents of the shopping basket. Is that practical? Are there other possible interpretations of what's needed here?