support array of tenant ids to getTenant

[Madvinking]

when a user is part of multiple tenants, to perform a mongo operation we need it to work on all tenant ids associated to the user.

currently, as a workaround, i return multiple models and execute the operation on all of them but it will be nice to pass an array of ids

[saqib-ahmed]

I have exactly the same requirement. Would be great to get this as a configuration option.