Update README.md

README.md

 - Bluetooth (Peripheral role. Don't use for Central only)
 - Background Refresh
 
-####General Usage
+##General Usage
 ```js
 const Permissions = require('react-native-permissions');
 
 //...
 ```
 
-####API
+##API
 
 _Permission statuses_ - `authorized`, `denied`, `restricted`, or `undetermined`
 
 npm install --save react-native-permissions
 ````
 
-###iOS
+##iOS
 * Run open node_modules/react-native-permissions
 * Drag ReactNativePermissions.xcodeproj into the Libraries group of your app's Xcode project
 * Add libReactNativePermissions.a to `Build Phases -> Link Binary With Libraries.