emailInputType should support `multiple` attribute, similar to ngList

[caitp]

The HTML5 standard gives email inputs a multiple attribute, which causes multiple emails to be parsed, and causes HTML5 constraint validation to behave differently. It would be good to be able to use ngList-ish behaviour using the proper HTML5 attribute.

It's maybe just a kind of nice thing to add

[Narretz]

See also:

#4233
#4295
#4549

Any pull should probably be based on #4344 (honor custom separators for ngList)

[RichardLitt]

It looks like #1866 is also relevant.

Why are these issues taking so long to be merged in? Is there anything I can do about it? Sorry, first time trying to help with the core, not sure about the proper protocol.

[binarykitchen]

+1 Hello folks - I would very welcome the multiple attribute here and hope someone can do it? Many thanks : )

[ilanbiala]

Multiple support would be nice!

[binarykitchen]

Any news on this one?