tomcat : Add find-links and shacache

stack/tomcat.cfg

@@ -3,6 +3,22 @@ extends =
   ../component/lxml-python/buildout.cfg
   ../component/java/buildout.cfg
   ../component/mysql-5.1/buildout.cfg
+  ../stack/shacache-client.cfg
+
+find-links +=
+    http://www.nexedi.org/static/packages/source/slapos.buildout/
+
+# Use only quite well working sites.
+allow-hosts =
+  *.nexedi.org
+  *.python.org
+  *.sourceforge.net
+  dist.repoze.org
+  effbot.org
+  github.com
+  peak.telecommunity.com
+  psutil.googlecode.com
+  www.dabeaz.com
 
 parts =
   template