Added Header, Icon and MessageModal. Refactor screens into directories.

mobile/src/Activity/Activity.js

@@ -0,0 +1,30 @@
+import React from 'react'
+import { StyleSheet, View, TouchableOpacity, Image, ScrollView } from 'react-native'
+import autobind from 'autobind-decorator'
+
+export class Activity extends React.Component {
+  static styles = StyleSheet.create({
+    container: {
+      height: '100%',
+      width: '100%',
+      backgroundColor: '#AAAAAA',
+    },
+  })
+
+  constructor(props) {
+    super(props)
+  }
+
+  _handlePushButton(event) {
+    this.props.history.goBack()
+  }
+
+  render() {
+    return (
+      <ScrollView style={Activity.styles.container}>
+        <View style={{ width: '94%', height: 300, backgroundColor: 'white', alignSelf: 'center', marginTop: '3%', shadowColor: 'gray', shadowOffset: { width: 2, height: 2 }, shadowRadius: 2, shadowOpacity: .5 }} />
+        <View style={{ width: '94%', height: 300, backgroundColor: 'white', alignSelf: 'center', marginTop: '3%', shadowColor: 'gray', shadowOffset: { width: 2, height: 2 }, shadowRadius: 2, shadowOpacity: .5 }} />
+      </ScrollView>
+    );
+  }
+}

mobile/src/Activity/index.js

@@ -0,0 +1 @@
+export { Activity } from './Activity'