Updated import statements to use the new `configparser` module name.

Updated the documentation to use the new name.
Revert addition of the stub entry for the old name.

Georg, I am reverting your changes since this commit should propagate
to py3k.

command/upload.py

@@ -10,7 +10,7 @@ from hashlib import md5
 import os
 import socket
 import platform
-import ConfigParser
+import configparser
 import httplib
 import base64
 import urlparse

config.py

@@ -5,7 +5,7 @@ that uses .pypirc in the distutils.command package.
 """
 import os
 import sys
-from ConfigParser import ConfigParser
+from configparser import ConfigParser
 
 from distutils.core import Command
 

dist.py

@@ -359,7 +359,7 @@ Common commands: (see '--help-commands' for more)
 
     def parse_config_files (self, filenames=None):
 
-        from ConfigParser import ConfigParser
+        from configparser import ConfigParser
 
         if filenames is None:
             filenames = self.find_config_files()