Extension Methods: Add missing whitespace in General Guidelines section

docs/csharp/programming-guide/classes-and-structs/extension-methods.md

@@ -95,7 +95,7 @@ using System.Linq;
 
  When using an extension method to extend a type whose source code you cannot change, you run the risk that a change in the implementation of the type will cause your extension method to break.  
 
- If you do implement extension methods for a given type, remember the followingpoints:  
+ If you do implement extension methods for a given type, remember the following points:  
 
 -   An extension method will never be called if it has the same signature as a method defined in the type.  
 
@@ -111,4 +111,4 @@ using System.Linq;
  [Conversion rules for Instance parameters and their impact](http://go.microsoft.com/fwlink/?LinkId=112385)   
  [Extension methods Interoperability between languages](http://go.microsoft.com/fwlink/?LinkId=112386)   
  [Extension methods and Curried Delegates](http://go.microsoft.com/fwlink/?LinkId=112387)   
- [Extension method Binding and Error reporting](http://go.microsoft.com/fwlink/?LinkId=112388)
+ [Extension method Binding and Error reporting](http://go.microsoft.com/fwlink/?LinkId=112388)