Add protobuf (https://github.com/google/protobuf) and nanopb (https://github.com/metormote/nanopb) to build example beerduino project (https://github.com/ilyevsky/beerduino) using platformio (http://docs.platformio.org/en/latest/).

proto/beerduino.proto

@@ -0,0 +1,14 @@
+
+import "nanopb.proto";
+
+package beerduino;
+
+message Ping {
+  required int32 id = 1;
+}
+
+message Echo {
+  required int32 id = 1;
+  optional string message = 2 [(nanopb).max_size = 40];
+}
+