fetch and display haveno daemon version in react

enable typescript
add haveno protobuf definitions to ./config
add envoy.yaml to ./config for envoy proxy config
add ./bin/build_protobuf.sh to generate and place grpc client
update readme

src/App.tsx

@@ -2,25 +2,59 @@ import React from 'react';
 import logo from './logo.svg';
 import './App.css';
 
-function App() {
-  return (
-    <div className="App">
-      <header className="App-header">
-        <img src={logo} className="App-logo" alt="logo" />
-        <p>
-          Edit <code>src/App.tsx</code> and save to reload.
-        </p>
-        <a
-          className="App-link"
-          href="https://reactjs.org"
-          target="_blank"
-          rel="noopener noreferrer"
-        >
-          Learn React
-        </a>
-      </header>
-    </div>
-  );
+/**
+ * These files are generated by protoc-gen-grpc-web (created with `sudo make install-plugin` in grpc-web) using the following command:
+ *
+ * `protoc -I=./ *.proto --js_out=import_style=commonjs:./ --grpc-web_out=import_style=commonjs,mode=grpcwebtext:./`
+ */
+const {GetVersionRequest} = require('./grpc_grpc_web_pb.js');
+const {GetVersionClient} = require('./grpc_pb.js');
+
+class App extends React.Component<{}, {daemonVersion: string}> {
+    
+  constructor(props: any) {
+    super(props);
+    this.state = {daemonVersion: ""};
+  }
+
+  render() {
+    return (
+      <div className="App">
+        <header className="App-header">
+          <img src={logo} className="App-logo" alt="logo" />
+          <p>
+            Haveno daemon version: {this.state.daemonVersion}
+          </p>
+          <p>
+            Edit <code>src/App.tsx</code> and save to reload!
+          </p>
+          <a
+            className="App-link"
+            href="https://reactjs.org"
+            target="_blank"
+            rel="noopener noreferrer"
+          >
+            Learn React
+          </a>
+        </header>
+      </div>
+    );
+  }
+  
+  async componentDidMount() {
+    this.setState({daemonVersion: await this.getDaemonVersion()});
+  }
+  
+  async getDaemonVersion(): Promise<string> {
+    let getVersionClient = new GetVersionClient('http://localhost:8080');
+    let request = new GetVersionRequest();
+    return new Promise(function(resolve, reject) {
+      getVersionClient.getVersion(request, {password: 'apitest'}, function(err: any, response: any) {
+        if (err) reject(err);
+        else resolve(response.getVersion());
+      });
+    });
+  }
 }
 
 export default App;