Channel aware customers & users (email address conflicts)

[BeepLoveKarki]

In a proper multivendor store, we need customers and users aware of channel, but in our case if we use same email address across multiple channels, same user is returned, updated, deleted.

Please suggest some easy way to tackle this right now!!!

And hope vendure makes it auto tackled in future release.

[michaelbromley]

Relates to #1329

[tonyellow]

I am interested in this specific feature also. I am trying to build a multi tenant solution where multiple channels can have the same customer with the same email. Maybe there should be an option to change the matching strategy to usernames instead of emails?