Added input sanitize functions. The new system works by merging $_GET and $_POST...

Added input sanitize functions. The new system works by merging $_GET and $_POST, running them through a unicode-safe htmlspecialchars() and storing it in _isso::input. Then this can be accessed; and proper data manipulation (intval(), floatval(), _isso::escape) can be run on it. _isso::escape uses a variety of escape functions from none (Magic Quotes on), to mysql_real_escape_string() (have a valid DB connection), to just addslashes() (neither of the previous two).