Accept either the username or the user's email address for login.

Per https://confluence.atlassian.com/x/ngR9GQ, I would like our Confluence instance to accept either the username or the user's email address for login. Since we do not use LDAP in our Confluence instance, I am following Adrian Reid's suggestion in the aforementioned webpage's conversation and am posting this feature request. I would think it would be straightforward since both the username and email address should be unique and are tied on the same Confluence user profile. Implementing this would avoid a lot of confusion as people can use either the username or email address to reset passwords but are required to use the username for login as we have set up our instance. I recall that we could have set up the instance to accept the email address. I don't want to be limited to either choice. Please set it up so that they could use either for login.