Revert "Created slides in chapter 3."

This reverts commit 8115d330eead8d1e29e9ec3171cc7b1034e9b1a5.

	new file:   images/Monty_open_door.svg
	deleted:    images/ln.png
	deleted:    images/logistic.png
	deleted:    images/sig_target.png
	modified:   index.html
	modified:   slide_config.js
	new file:   template.html
	modified:   theme/css/additional.css
	modified:   theme/scss/additional.scss