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/client.rs

@@ -170,6 +170,12 @@ impl Builder {
         self
     }
 
+    /// Set the max frame size of received frames.
+    pub fn max_frame_size(&mut self, max: u32) -> &mut Self {
+        self.settings.set_max_frame_size(Some(max));
+        self
+    }
+
     /// Bind an H2 client connection.
     ///
     /// Returns a future which resolves to the connection value once the H2
@@ -203,6 +209,10 @@ where
         // Create the codec
         let mut codec = Codec::new(io);
 
+        if let Some(max) = self.settings.max_frame_size() {
+            codec.set_max_recv_frame_size(max as usize);
+        }
+
         // Send initial settings frame
         codec
             .buffer(self.settings.clone().into())