Move the action of loading the configuration to the IdleConf module

rather than the idle.py script.  This has advantages and
disadvantages; the biggest advantage being that we can more easily
have an alternative main program.

Tools/idle/IdleConf.py

@@ -110,3 +110,4 @@ def load(dir):
                    os.path.join(homedir, ".idle")))
 
 idleconf = IdleConfParser()
+load(os.path.dirname(__file__))

Tools/idle/idle.py

 #! /usr/bin/env python
 
-import os
-import sys
-import IdleConf
-
-idle_dir = os.path.dirname(IdleConf.__file__)
-IdleConf.load(idle_dir)
-
-# defer importing Pyshell until IdleConf is loaded
 import PyShell
 PyShell.main()