Format code snippets

Author: drewnoakes

docs/extensibility/registering-and-unregistering-vspackages.md

@@ -27,7 +27,9 @@ You use attributes to register a VSPackage, but
 [PackageRegistration(UseManagedResourcesOnly = true)]  
 [Guid("0B81D86C-0A85-4f30-9B26-DD2616447F95")]  
 public sealed class BasicPackage : Package  
-{. . .}  
+{
+    // ...
+}  
 ```  
 
 ## Unregister an extension  
@@ -57,9 +59,9 @@ The following code shows how to create a new registration attribute.
 
 ```csharp  
 [AttributeUsage(AttributeTargets.Class, Inherited = true, AllowMultiple = false)]  
-    public class CustomRegistrationAttribute : RegistrationAttribute  
-    {  
-    }  
+public class CustomRegistrationAttribute : RegistrationAttribute  
+{  
+}  
 ```  
 
  The <xref:System.AttributeUsageAttribute> is used on attribute classes to specify the program element (class, method, etc.) to which the attribute pertains, whether it can be used more than once, and whether it can be inherited.  
@@ -107,7 +109,7 @@ public override void Register(RegistrationAttribute.RegistrationContext context)
     {  
         if (packageKey != null)  
             packageKey.Close();  
-                }  
+    }  
 }  
 
 public override void Unregister(RegistrationContext context)