Restrict source by allow-hosts.

Most of required eggs are anyway available on pypi, which is much more
reliable than all scattered sources. Idea by Leonardo.

software/zabbix-agent/software.cfg

@@ -13,6 +13,12 @@ parts =
   eggs
   template
 
+# Use only quite well working sites.
+allow-hosts =
+  *.nexedi.org
+  *.python.org
+  *.sourceforge.net
+
 [eggs]
 recipe = zc.recipe.egg
 eggs =