Update to new Expo SDK

- removed native-base dependency

state/Reducer.js

@@ -2,7 +2,6 @@ import { combineReducers } from 'redux';
 import { deviceStateReducer } from "./DeviceReduxCoupling";
 
 export const CHANGE_USER_NAME = "SET_USERNAME";
-export const CHANGE_THEME = "CHANGE_THEME";
 export const RESET_DEVICE_DATA = "RESET_DEVICE_DATA";
 
 
@@ -11,11 +10,6 @@ export const changeUsername = newUsername => ({
     newUserName: newUsername,
 });
 
-export const changeTheme = newThemeName => ({
-    type: CHANGE_THEME,
-    newThemeName: newThemeName
-});
-
 export const startSession = () => ({
     type: START_SESSION
 });
@@ -52,8 +46,6 @@ const INITIAL_SETTINGS = {
 
 const settingsReducer = (state = INITIAL_SETTINGS, action) => {
     switch (action.type) {
-        case CHANGE_THEME:
-            return { ...state, theme: action.newThemeName };
         case CHANGE_USER_NAME:
             return { ...state, username: action.newUsername };
         default: