Basic auth should allow for multiple user/password pairs

**Is your feature request related to a problem? Please describe.**
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
I need to be able to block/allow access to multiple users. At each point in time, one or more might need to be blocked while others need not. I have not need for a SSO type solution, which is an overkill in my current situation (limiting access to various beta testers). Currently, basic auth only allows for single "password" value, not even a user name. This means that one can either restrict access to everyone or no one.

**Describe the solution you'd like**
It would be great if the one could configure, via a file (as is possible for other authentication methods), to allow for multiple user/password pairs. This configuration would get reloaded every time the file is updated and will be in effect from that moment on. That will allow revoking/granting access for users, as needed.

**Describe alternatives you've considered**
1. Using an SSO provider (but that's really an overkill).