php refactor - strong rng cleanup

This refactors the php example into a class and allows relatively transparent inclusion into existing scripts. See form.php.

It also updates the aes random key generation to use strong crypto where available, which removes the need for pbkdf2, which increases performance.

At this point I am required to create a javascript module that does not depend on jQuery (or any framework).  I will backport what is relevant, if interested follow https://github.com/j-c-m/javascrypt, it will be all mit licensed as well.