Merge branch '348-password-screen' into 'master'

Removes logo and adds header on the main login screen

Closes #348

See merge request bloodyhealth/drip!211

components/password-prompt.js

 import React, { Component } from 'react'
-import { View, TextInput, TouchableOpacity, Alert, Image } from 'react-native'
+import { View, TextInput, TouchableOpacity, Alert } from 'react-native'
 import nodejs from 'nodejs-mobile-react-native'
 import { saveEncryptionFlag } from '../local-storage'
 import AppText from './app-text'
+import Header from './header'
 import styles from '../styles'
-import { passwordPrompt as labels, shared } from '../i18n/en/labels'
+import { passwordPrompt as labels, shared, menuTitles } from '../i18n/en/labels'
 import { requestHash, deleteDbAndOpenNew, openDb } from '../db'
 
 export default class PasswordPrompt extends Component {
@@ -87,12 +88,10 @@ export default class PasswordPrompt extends Component {
   render() {
     return (
       <View flex={1}>
+        <Header title={menuTitles.PasswordPrompt.toLowerCase()} />
         {this.state.showPasswordPrompt &&
           <View style={styles.passwordPromptPage}>
-            <Image
-              source={require('../assets/drip_small.png')}
-              style={styles.passwordPromptImage}
-            />
+
             <TextInput
               onChangeText={val => this.setState({ password: val })}
               style={styles.passwordPromptField}

i18n/en/labels.js

@@ -50,6 +50,7 @@ export const menuTitles = {
   Chart: 'Chart',
   Stats: 'Stats',
   Settings: 'Settings',
+  PasswordPrompt: 'Drip'
 }
 
 export const stats = {

styles/index.js

@@ -401,6 +401,8 @@ export default StyleSheet.create({
   },
   passwordPromptPage: {
     padding: 30,
+    flex: 1,
+    justifyContent: 'center',
     alignItems: 'center'
   },
   passwordPromptField: {