Linter update (#1777)

* Update eslint config

* Applied linter to lib

* Applied eslint config to CliClient/app

* Removed prettier due to https://github.com/prettier/prettier/pull/4765

* First pass on test units

* Applied linter config to test units

* Applied eslint config to clipper

* Applied to plugin dir

* Applied to root of ElectronClient

* Applied on RN root

* Applied on CLI root

* Applied on Clipper root

* Applied config to tools

* test hook

* test hook

* test hook

* Added pre-commit hook

* Applied rule no-trailing-spaces

* Make sure root packages are installed when installing sub-dir

* Added doc

ReactNativeClient/App.js

@@ -1,49 +0,0 @@
-/**
- * Sample React Native App
- * https://github.com/facebook/react-native
- *
- * @format
- * @flow
- */
-
-import React, {Component} from 'react';
-import {Platform, StyleSheet, Text, View} from 'react-native';
-
-const instructions = Platform.select({
-  ios: 'Press Cmd+R to reload,\n' + 'Cmd+D or shake for dev menu',
-  android:
-    'Double tap R on your keyboard to reload,\n' +
-    'Shake or press menu button for dev menu',
-});
-
-type Props = {};
-export default class App extends Component<Props> {
-  render() {
-    return (
-      <View style={styles.container}>
-        <Text style={styles.welcome}>Welcome to React Native!</Text>
-        <Text style={styles.instructions}>To get started, edit App.js</Text>
-        <Text style={styles.instructions}>{instructions}</Text>
-      </View>
-    );
-  }
-}
-
-const styles = StyleSheet.create({
-  container: {
-    flex: 1,
-    justifyContent: 'center',
-    alignItems: 'center',
-    backgroundColor: '#F5FCFF',
-  },
-  welcome: {
-    fontSize: 20,
-    textAlign: 'center',
-    margin: 10,
-  },
-  instructions: {
-    textAlign: 'center',
-    color: '#333333',
-    marginBottom: 5,
-  },
-});