basic layout of main page

- consists of the navbar, chat, and adspace components

app/screens/main/chat.js

@@ -0,0 +1,29 @@
+/*
+ * Chat component within Main
+ */
+import React, { Component } from 'react';
+import {
+  Dimensions,
+  View,
+  Text,
+} from 'react-native';
+import {
+  Actions
+} from 'react-native-router-flux';
+
+const windowWidth = Dimensions.get('window').width;
+const windowHeight = Dimensions.get('window').height;
+
+type Props = {};
+export default class Chat extends Component<Props> {
+  render() {
+    return (
+      <View style={styles.container}>
+        <Text>chat</Text>
+      </View>
+    );
+  }
+}
+
+const styles = {
+}