Linking the same names to multiple SeqCode Registry users

[MarikePalmer]

Ensures continuity in contact when users leave current positions etc - more than one submitter for a name, in effect.

[lmrodriguezr]

Please note that both the email address and the affiliation can be changed, but multiple submitters per name are indeed a desirable feature

[lmrodriguezr]

Probably easier to model at the Registry List level (instead of the name level)