update old crawlera link

pablohoffman · pablohoffman · commit 545c4224f9d7 · 2015-05-25T16:01:54.000-03:00
diff --git a/docs/topics/practices.rst b/docs/topics/practices.rst
@@ -254,4 +254,4 @@ If you are still unable to prevent your bot getting banned, consider contacting
 .. _Google cache: http://www.googleguide.com/cached_pages.html
 .. _testspiders: https://github.com/scrapinghub/testspiders
 .. _Twisted Reactor Overview: http://twistedmatrix.com/documents/current/core/howto/reactor-basics.html
-.. _Crawlera: http://crawlera.com
+.. _Crawlera: http://scrapinghub.com/crawlera
