Tweak license page to explicitly say that zero clause BSD is functionally equivalent...

Tweak license page to explicitly say that zero clause BSD is functionally equivalent to placing the code in the public domain.

This license variant looks like BSD, but is an unrestricted permission grant that doesn't require you to copy specific license text into derivative works. (The second paragraph is about something we DON'T do, I.E. provide any sort of warantee, and is just boilerplate from BSD to make it look like a BSD license.)