Feature Request: Alt attribute for profile pictures

Currently, profile pictures (`.profile-picture`) have no way of setting an alt attribute for them. Could profile photos please have a way to set the alt attribute thanks.

This could look like this:

Thanks,

Tristie

I added your feature request to issues in my fork of vpub: https://github.com/hugmouse/vpub-plus/issues/6

Hope you don't mind. I might add it in the future.