Add some READMEs for examples

Examples/Echo/README.md

@@ -0,0 +1,18 @@
+This directory contains a simple echo server that can be used to
+verify interoperability of Swift and Go gRPC servers.
+
+The Go directory contains a Go client and server. The server
+listens on localhost:8080 and the client connects to this by
+default but can be pointed at other servers using the "-a" 
+command-line option.
+
+The Swift directory contains a Mac app that contains a Swift
+client and server. The server starts with the app and listens
+on localhost:8081. The client runs in a window and connects by
+default to this port but can be pointed at other servers using
+the address field in the Echo window.
+
+When the Go server and Mac app are running on the same machine,
+both clients can be used to connect to both servers.
+
+

README.md

@@ -7,13 +7,19 @@ Swift wrappers for the C gRPC API that can be used to build
 higher-level structures supporting streaming and nonstreaming
 gRPC APIs. 
 
-The current version contains NO protocol buffer support (yet).
+Preliminary protocol buffer support is provided in the QuickProto
+library. This simple Swift library provides an API for building and
+parsing protocol buffers with no generated code.
 
 Code is provided for both gRPC clients and servers,
 and it can be built either with Xcode or the Swift Package Manager.
 The Xcode build is demonstrated with [Sessions](Examples/Sessions), 
 a sample Mac app that can be used to create and run multiple
 concurrent servers and clients. 
+
+Other examples include [StickyNotes](Examples/StickyNotes) and 
+[Echo](Examples/Echo).
+
 Swift Package Manager builds are demonstrated on Linux using 
 the instructions in the [Packages](Packages) directory.