(rust) prost: added simple protobuf sample for testing

rust/proto/src/lib.rs

@@ -0,0 +1,5 @@
+// pub mod protest;
+
+pub mod protest {
+    include!(concat!(env!("OUT_DIR"), "/protest.rs"));
+}

rust/proto/src/protest.proto

@@ -0,0 +1,19 @@
+syntax = "proto3";
+
+package protest;
+
+message Payload {
+  /*
+   * The package index of the given message, so which part of the message is
+   * currently being loaded.
+   */
+  uint64 index = 1;
+  /*
+   * The total block count.
+   */
+  uint64 blocks = 2;
+  /*
+   * The resulting payload to be loaded
+   */
+  bytes payload = 3;
+}