Removed duplicated commentary starts and added a proper readme file for GitHub

There was a lot of duplicated "/*" in the Lua files and the readme file was correctly formated with the GitHub Flavored Markdown, but it was inside a ".txt" file, so I copied it into a new file with the ".md" extension.

In the text files I only removed the "/*" and keeped the dashed line, looks like you tried to make the text inside it looks like a header, so the purpose was not modified.

With text files I mean the two "readme.txt" and the other "how to make a module.txt"