{master} only send welcome email if no confirmation email was sent
{master} only send welcome email if no confirmation email was sent

as to send ~500k fewer emails per month.

arex1337/lila,luanlv/lila,arex1337/lila,luanlv/lila,arex1337/lila,luanlv/lila,arex1337/lila,arex1337/lila,luanlv/lila,luanlv/lila,luanlv/lila,arex1337/lila,luanlv/lila,arex1337/lila