Improved guide for creating different app keys more clear (#226)

* Modified Issue_Template to be more descriptive

* Some minor changes to decription field

* Improved messages to make intention of creating different apps for different platforms more clear

Due to multiple requests in discord chanel, microsoft/react-native-code-push#723, microsoft/react-native-code-push#717

* FIxed spelling for Readme

README.md

@@ -66,9 +66,9 @@ With the CodePush plugin installed, configure your app to use it via the followi
     </platform>
     ```
 
-    As a reminder, these keys are generated for you when you created your CodePush app via the CLI. If you need to retrieve them, you can simply run `code-push deployment ls APP_NAME -k`, and grab the key for the specific deployment you want to use (e.g. `Staging`, `Production`).
+    As a reminder, these keys are generated for you when you created your CodePush app via the CLI. If you need to retrieve them, you can simply run `code-push deployment ls APP_NAME -k`, and grab the key for the specific deployment you want to use (e.g. `Staging`, `Production`). 
 
-    *NOTE: We [recommend](http://microsoft.github.io/code-push/docs/cli.html#link-4) creating a separate CodePush app for iOS and Android, which is why the above sample illustrates declaring seperate keys for Android and iOS. If you're only developing for a single platform, then you only need to specify the deployment key for either Android or iOS, so you don't need to add the additional `<platform>` element as illustrated above.*
+    *NOTE: You [must](http://microsoft.github.io/code-push/docs/cli.html#link-4) create a separate CodePush app for iOS and Android, which is why the above sample illustrates declaring seperate keys for Android and iOS. If you're only developing for a single platform, then you only need to specify the deployment key for either Android or iOS, so you don't need to add the additional `<platform>` element as illustrated above.*
 
 2. If you're using an `<access origin="*" />` element in your `config.xml` file, then your app is already allowed to communicate with the CodePush servers and you can safely skip this step. Otherwise, add the following additional `<access />` elements: