Fix PHP docker configuration

[therealgaxbo]

The previous config piped all fizzbuzz output from the container to the host. This is inherently slow, but as docker logs all stdout by default it's glacial. Instead, run pv inside the container.

To make docker play well with score.py I had to trap the script exiting and manually docker kill the container - perhaps there's a better way?

Also changed the image to use a regular (non ZTS) php build, and enable the JIT compiler.