@ olafsg this doesn't have nothing with ranking, seo, google updates.
@ theKpages yes, somewhere on page 4 is last version. there is no need to update nothing in code, this is simply redirector to specific rules, easy to set your own ip ranges, user agents, host names. Everyone has their specific goals so I am even not trying to set universal list of bad bots or this or that, look in logs and see what to block and thats it.
There is small .htaccess file to protect listing of files and reading text files. Also empty index.php can do a trick, or script file rename to index.php .
Robots.txt is absolutely depreciated "protection", just a text file with directives for "good" bots what not to index. They can listen, or not. I have seen scripts that are specifically looking files and scanning folders that are "blocked" in robots.txt