Better splashscreens. Updated development_guide to indicate to use node v6 and cordova 9

config.xml

@@ -98,6 +98,9 @@
         <splash height="1024" src="resources/ios/splash/Default-Portrait~ipad.png" width="768" />
         <splash height="960" src="resources/ios/splash/Default@2x~iphone.png" width="640" />
         <splash height="480" src="resources/ios/splash/Default~iphone.png" width="320" />
+        <splash height="2048" src="resources/ios/splash/Default-Landscape@~ipadpro.png" width="2732" />
+        <splash height="2732" src="resources/ios/splash/Default-Portrait@~ipadpro.png" width="2048" />
+        <splash height="2732" src="resources/ios/splash/Default@2x~universal~anyany.png" width="2732" />
         <edit-config file="*-Info.plist" mode="merge" target="NSCameraUsageDescription">
             <string>To scan QRCode</string>
         </edit-config>

doc/development_guide.md

@@ -16,14 +16,14 @@ To build Cesium, you will have to:
 
 > Then reload your terminal, for instance by executing the commande `bash`
 
-  - Configure NodeJS to use a version 5: (**WARNING**: upper version will NOT work !) 
+  - Configure NodeJS to use a version 6: (**WARNING**: upper version will NOT work !) 
 ```
-  nvm install 5
+  nvm install 6
 ```
       
   - Installing node.js build tools:
 ```
-   npm install -g gulp bower@1.8.0 cordova@6.5.0 ionic@1.7.16
+   npm install -g gulp bower@1.8.0 cordova@9.0.0 ionic@1.7.16
 ```
    
 ## Get the source code and dependencies