chore: Clean public directory (#262)

* chore: clean public dir

Remove .htaccess and config.php, as both were referencing files that do not
exist
anymore (app.php)

Write explicit rule in robots.txt to avoid future confusion (rule with no
allow/disallow is ignored)

* Write explicit rule in robots.txt to avoid future confusion (rule with no
allow/disallow is ignored)

Author: smnandre