Foundation.php: introduced description method

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Message.php: fixed wrong template code

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Foundation.php: improved NSInvocation and forwardInvocation

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>