.htaccess でこれらの書き換えルールを作成するには?
www.mysite.com/123 -> www.mysite.com/project.php?id=123
www.mysite.com/123/ -> www.mysite.com/project.php?id=123
www.mysite.com/about -> www.mysite.com/about/
www.mysite.com/about/ -> www.mysite.com/about/
www.mysite.com/123.php -> www.mysite.com/123.php