Add WindowScale option

Signed-off-by: Gregory Detal <gregory.detal@uclouvain.be>
Add PushLayer(Layer *) to Packet objects

Signed-off-by: Gregory Detal <gregory.detal@uclouvain.be>
Add Fields accessibility functions to Layer

Signed-off-by: Gregory Detal <gregory.detal@uclouvain.be>
Add MPTCP option parsing

Signed-off-by: Gregory Detal <gregory.detal@uclouvain.be>