add support for configuring max frame size

- Adds `max_frame_size` to client and server builders
- Pushes max_frame_size into Codec
- Detects when the Codec triggers an error from a frame too big
- Sends a GOAWAY when FRAME_SIZE_ERROR is encountered reading a frame

src/codec/framed_write.rs

@@ -227,7 +227,7 @@ impl<T, B> FramedWrite<T, B> {
 
     /// Set the peer's max frame size.
     pub fn set_max_frame_size(&mut self, val: usize) {
-        assert!(val <= frame::MAX_MAX_FRAME_SIZE);
+        assert!(val <= frame::MAX_MAX_FRAME_SIZE as usize);
         self.max_frame_size = val as FrameSize;
     }