fix(sourcemaps): commented out sourcemaps for now & tweaked PHP

At the moment, Autoprefixer is eating sourcemaps output by LESS.
I don't know what's going on, and I don't currently have time to
fix it, so I'm just leaving them out for now.

The local address for the PHP server has been updated to
127.0.0.1 and the `open` flag has been set to `true`.