Fixed typo en_ftp_user.lng

Author: Alex Wink

interface/web/sites/lib/lang/en_ftp_user.lng

@@ -18,7 +18,7 @@ $wb["active_txt"] = 'Active';
 $wb["limit_ftp_user_txt"] = 'The max. number of FTP users for your account is reached.';
 $wb["username_error_empty"] = 'Username is empty.';
 $wb["username_error_unique"] = 'The username must be unique.';
-$wb["username_error_regex"] = 'The username contains charachters that are not allowed.';
+$wb["username_error_regex"] = 'The username contains characters that are not allowed.';
 $wb["quota_size_error_empty"] = 'Quota is empty.';
 $wb["uid_error_empty"] = 'UID empty.';
 $wb["uid_error_empty"] = 'GID empty.';