Fix two spaces between sententes on README.rdoc.

README.rdoc

@@ -3,11 +3,11 @@
 Rails is a web-application framework that includes everything needed to create
 database-backed web applications according to the {Model-View-Controller (MVC)}[http://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller] pattern.
 
-Understanding the MVC pattern is key to understanding Rails.  MVC divides your application
+Understanding the MVC pattern is key to understanding Rails. MVC divides your application
 into three layers, each with a specific responsibility.
 
 The View layer is composed of "templates" that are responsible for providing 
-appropriate representations of your application's resources.  Templates
+appropriate representations of your application's resources. Templates
 can come in a variety of formats, but most view templates are HTML with embedded Ruby 
 code (.erb files). 
 
@@ -21,7 +21,7 @@ provided by the ActiveModel module. You can read more about Active Record in its
 {README}[link:files/activerecord/README_rdoc.html].
 
 The Controller layer is responsible for handling incoming HTTP requests and providing a 
-suitable response.  Usually this means returning HTML, but Rails controllers can also 
+suitable response. Usually this means returning HTML, but Rails controllers can also
 generate XML, JSON, PDFs, mobile-specific views, and more. Controllers manipulate models 
 and render view templates in order to generate the appropriate HTTP response.