Document JSONP

Signed-off-by: Clement Escoffier <clement.escoffier@gmail.com>
Remove duplicated documentation

Signed-off-by: Clement Escoffier <clement.escoffier@gmail.com>
Document new negotiation methods

Signed-off-by: Clement Escoffier <clement.escoffier@gmail.com>
Document testing

Signed-off-by: Clement Escoffier <clement.escoffier@gmail.com>