Torsten step 1

This is the first step in a series describing my attempts to build a roughlike called "Torsten" in pure JavaScript. There are many tutorials explaining how to design a rouglike, such as this excellent one:

https://nluqo.github.io/broughlike-tutorial/

Actually, this is a broughlike, which is a variation of a roughlike based on games by Michael Brough.

In this first step I have designed some sprites of the protagonist Torsten and two background tiles, namely a floor and a wall. All code have been borrowed from the tutorial above. So far I just followed stage 1 & 2 in the tutorial...