Good catch. I'll clarify in the docs, but a link back to the project somewhere accessible and on the same domain will suffice. I'm also happy to make exceptions on a case by case basis, also in accordance with the CC BY 3.0.
In fact, now I'm curious. You took the Glyphicons set and effectively copied it, yes? I don't see a link to Glyphicons on your site, which their license requires. Aren't you therefore infringing their copyright by creating a derivative work without license?
I used the classes from the Glyphicons set for backwards compatibility, but every icon was designed from scratch. If you look closely, you'll notice many of them are quite different.
https://creativecommons.org/publicdomain/zero/1.0/
Up to you, though.Actually, what's the advantage of using a commercial, attribution license over a BSD?