Fix warning on startup if user didn't have personal copies of cluster config.

We use the builtin defaults in this case, we were just missing searching in
our own paths.

Also suppress deprecation warnings from Twisted.

IPython/kernel/clusterdir.py

@@ -20,6 +20,7 b' from __future__ import with_statement'
 import os
 import shutil
 import sys
+import warnings
 
 from twisted.python import log
 
@@ -27,13 +28,25 b' from IPython.core import release'
 from IPython.config.loader import PyFileConfigLoader
 from IPython.core.application import Application
 from IPython.core.component import Component
+from IPython.utils.genutils import get_ipython_dir, get_ipython_package_dir
 from IPython.utils.traitlets import Unicode, Bool
 from IPython.utils import genutils
 
 #-----------------------------------------------------------------------------
-# Imports
+# Warnings control
 #-----------------------------------------------------------------------------
+# Twisted generates annoying warnings with Python 2.6, as will do other code
+# that imports 'sets' as of today
+warnings.filterwarnings('ignore', 'the sets module is deprecated',
+                        DeprecationWarning )
 
+# This one also comes from Twisted
+warnings.filterwarnings('ignore', 'the sha module is deprecated',
+                        DeprecationWarning)
+
+#-----------------------------------------------------------------------------
+# Classes and functions
+#-----------------------------------------------------------------------------
 
 class ClusterDirError(Exception):
     pass
@@ -352,9 +365,6 b' class ApplicationWithClusterDir(Application):'
         self.default_config.Global.cluster_dir = self.cluster_dir
         self.command_line_config.Global.cluster_dir = self.cluster_dir
 
-        # Set the search path to the cluster directory
-        self.config_file_paths = (self.cluster_dir,)
-
     def find_config_file_name(self):
         """Find the config file name for this application."""
         # For this type of Application it should be set as a class attribute.
@@ -362,8 +372,11 b' class ApplicationWithClusterDir(Application):'
             self.log.critical("No config filename found")
 
     def find_config_file_paths(self):
-        # Set the search path to the cluster directory
-        self.config_file_paths = (self.cluster_dir,)
+        # Include our own config directory last, so that users can still find
+        # our shipped copies of builtin config files even if they don't have
+        # them in their ipython cluster directory.
+        conf_dir = os.path.join(get_ipython_package_dir(), 'config', 'default')
+        self.config_file_paths = (self.cluster_dir, conf_dir)
 
     def pre_construct(self):
         # The log and security dirs were set earlier, but here we put them