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* Add `set -x` to long command chains to show individiual commands
* Add `--no-install-recommends` to `apt-get install` calls
* Use `apt-get purge --auto-remove` instead of `apt-get remove`
* Add `-f` to `curl` commands to immediately fail on status code >= 400

Also fixes rm -rf paths for apt lists

I must have thought this was needed with an earlier version of the php:apache
base image. Not sure if it ever actually was.

Fixes #7

* Eliminates .htaccess file creation in entrypoint
* Restricts PHP script execution under /var/www/html/images (fixes #5)

Picks up PID-cleaning behavior from https://github.com/docker-library/php/pull/59

Fixes #6

Thanks!

Closes #2