iOS support: Fix "Missing attestations" message on AppStoreConnect. Added specific App ID for iOS. iOS 13 compatibility. Fix NPM install for minisodium.

• Added ITSAppUsesNonExemptEncryption key with value NO in Info.plist to avoid "Missing attestations" message on AppStoreConnect.
• Updated cordova config to include specific "org.duniter.cesium" App ID for iOS.
• Upgraded to Cordova 9 and Cordova iOS 5.x. Cordova Android is still using 6.x version (6.4.0).
• Using WKWebView only fork of cordova-ios to prepare for iOS 13 (Fix issue #661 of cordova-ios. Pull request opened on official cordova-ios repository: https://github.com/apache/cordova-ios/pull/663).
• Removed cordova-plugin-inappbrowser at it wasn't used anywhere.

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