docs: update docs regarding babel and flow. fixes callstack#392

Author: satya164

Diff for: .prettierrc

@@ -0,0 +1,5 @@
+
+singleQuote: true
+tabWidth: 2
+trailingComma: "es5"
+useTabs: false

Diff for: docs/pages/2.getting-started.md

@@ -23,21 +23,24 @@ If you use CRNA or Expo, you don't need to install vector icons. But you will ne
 
 ```json
 {
-  "presets": ["expo"]
+  "presets": ["babel-preset-expo"]
 }
 ```
 
-To get smaller bundle size by excluding modules you don't use, you can use our optional babel plugin. The plugin automatically rewrites the import statements so that only the modules you use are imported instead of the whole library. Add `react-native-paper/babel` to the `plugins` section in your `.babelrc`:
+To get smaller bundle size by excluding modules you don't use, you can use our optional babel plugin. The plugin automatically rewrites the import statements so that only the modules you use are imported instead of the whole library. Add `react-native-paper/babel` to the `plugins` section in your `.babelrc` for production environment. It should look like this:
 
 ```json
 {
-  "plugins": [
-    "react-native-paper/babel"
-  ]
+  "presets": ["babel-preset-react-native"],
+  "env": {
+    "production": {
+      "plugins": ["react-native-paper/babel"]
+    }
+  }
 }
 ```
 
-If you created your project using CRNA or Expo, you'll have an `env` section. You can create a new `production` key and place it below so it looks like this:
+If you created your project using CRNA or Expo, it'll look something like this:
 
 ```json
 {
@@ -55,6 +58,14 @@ If you created your project using CRNA or Expo, you'll have an `env` section. Yo
 
 **Note:** The plugin only works if you are importing the library using ES2015 import statements and not with `require`.
 
+If you're using Flow for typechecking your code, you need to add the following under the `[options]` section in your `.flowconfig`:
+
+```ini
+module.file_ext=.js
+module.file_ext=.android.js
+module.file_ext=.ios.js
+```
+
 ## Usage
 
 Wrap your root component in `Provider` from `react-native-paper`. If you have a vanilla React Native project, it's a good idea to add it in the component which is passed to `AppRegistry.registerComponent`. This will usually be in the `index.js` file. If you have a CRNA or Expo project, you can do this inside the exported component in the `App.js` file.