Fix readme to remove broken link for the April's End User Preview (for Visual...

Fix readme to remove broken link for the April's End User Preview (for Visual studio 2013), which is no longer available.

README.md

@@ -23,8 +23,7 @@ which has the latest features built-in.
 [prebuilt Azure VM images](http://blogs.msdn.com/b/visualstudioalm/archive/2014/06/04/visual-studio-14-ctp-now-available-in-the-virtual-machine-azure-gallery.aspx) 
 with VS 2015 Preview already installed.
 
-* You can also try April's [End User Preview](http://go.microsoft.com/fwlink/?LinkId=394641), 
-which installs on top of Visual Studio 2013. *(Note: The VS 2013 preview is quite out of date, and is no longer being updated.)*
+* Roslyn is no longer available for Visual Studio 2013.
 
 ### Build tools that understand C# and Visual Basic