remove dead code from <App>. closes #1718

src/components/App.js

 import React, { Component } from 'react';
-import { compose } from 'redux';
-import { connect } from 'react-redux';
-
 import CssBaseline from '@material-ui/core/CssBaseline';
-import { actions } from '../store';
 import WorkspaceControlPanel from './WorkspaceControlPanel';
 import ConnectedWorkspace from './Workspace';
 import ns from '../config/css-ns';
@@ -12,7 +8,7 @@ import ns from '../config/css-ns';
  * This is the top level Mirador component.
  * @prop {Object} manifests
  */
-export class App extends Component {
+class App extends Component {
   /**
    * render
    * @return {String} - HTML markup for the component
@@ -28,27 +24,4 @@ export class App extends Component {
   }
 }
 
-/**
- * mapStateToProps - to hook up connect
- * @memberof App
- * @private
- */
-const mapStateToProps = state => (
-  {
-    manifests: state.manifests,
-  }
-);
-
-/**
- * mapDispatchToProps - used to hook up connect to action creators
- * @memberof App
- * @private
- */
-const mapDispatchToProps = { fetchManifest: actions.fetchManifest };
-
-const enhance = compose(
-  connect(mapStateToProps, mapDispatchToProps),
-  // further HOC go here
-);
-
-export default enhance(App);
+export default App;