style(): unify docs and spacing (#1448)

* typo(barcode-scanner): fixe circle lint error

* typo(docs):  Unified the documentations

In some plugins the typescript markup was missing.
I also unified the console.log string from console.log("hello") to console.log('Hello') so any plugin page look the same.

src/@ionic-native/plugins/file-opener/index.ts

@@ -7,7 +7,7 @@ import { Plugin, Cordova, IonicNativePlugin } from '@ionic-native/core';
  * This plugin will open a file on your device file system with its default application.
  *
  * @usage
- * ```
+ * ```typescript
  * import { FileOpener } from '@ionic-native/file-opener';
  *
  * constructor(private fileOpener: FileOpener) { }
@@ -41,7 +41,7 @@ export class FileOpener extends IonicNativePlugin {
     successName: 'success',
     errorName: 'error'
   })
-  open(filePath: string, fileMIMEType: string): Promise<any> {return; }
+  open(filePath: string, fileMIMEType: string): Promise<any> { return; }
 
   /**
    * Uninstalls a package
@@ -53,7 +53,7 @@ export class FileOpener extends IonicNativePlugin {
     successName: 'success',
     errorName: 'error'
   })
-  uninstall(packageId: string): Promise<any> {return; }
+  uninstall(packageId: string): Promise<any> { return; }
 
   /**
    * Check if an app is already installed
@@ -65,6 +65,6 @@ export class FileOpener extends IonicNativePlugin {
     successName: 'success',
     errorName: 'error'
   })
-  appIsInstalled(packageId: string): Promise<any> {return; }
+  appIsInstalled(packageId: string): Promise<any> { return; }
 
 }