merged branch royopa/patch-1 (PR #789)

This PR was submitted for the master branch but it was merged into the 1.0 branch instead (closes #789).

Discussion
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Update intro.rst - Included links to Symfony2, Pimple and Sinatra

Included links to Symfony2, Pimple and Sinatra

Commits
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f9c13a1 Update intro.rst - Included links to Symfony2, Pimple and Sinatra

doc/intro.rst

@@ -2,7 +2,7 @@ Introduction
 ============
 
 Silex is a PHP microframework for PHP 5.3. It is built on the shoulders of
-Symfony2 and Pimple and also inspired by sinatra.
+`Symfony2`_ and `Pimple`_ and also inspired by `Sinatra`_.
 
 A microframework provides the guts for building simple single-file apps. Silex
 aims to be:
@@ -46,3 +46,6 @@ Installing Silex is as easy as it can get. `Download`_ the archive file,
 extract it, and you're done!
 
 .. _Download: http://silex.sensiolabs.org/download
+.. _Symfony2: http://symfony.com/
+.. _Pimple: http://pimple.sensiolabs.org/
+.. _Sinatra: http://www.sinatrarb.com/