minor #1628 Replace IRC with StackOverflow/GitHub (hkdobrev)

This PR was merged into the 2.3.x-dev branch.

Discussion
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Replace IRC with StackOverflow/GitHub

Closes #1626

Commits
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13c53c5 Replace IRC with StackOverflow/GitHub

README.rst

@@ -52,10 +52,12 @@ To run the test suite, you need `Composer`_ and `PHPUnit`_:
     composer install
     phpunit
 
-Community
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+Support
+-------
+
+If you have a configuration problem use the `silex tag`_ on StackOverflow to ask a question.
 
-Check out #silex-php on irc.freenode.net.
+If you think there is an actual problem in Silex, please `open an issue`_ if there isn't one already created.
 
 License
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@@ -67,3 +69,5 @@ Silex is licensed under the MIT license.
 .. _PHPUnit:            https://phpunit.de
 .. _silex.zip:          http://silex.sensiolabs.org/download
 .. _documentation:      http://silex.sensiolabs.org/documentation
+.. _silex tag:      https://stackoverflow.com/questions/tagged/silex
+.. _open an issue:      https://github.com/silexphp/Silex/issues/new