Documentation updates for urllib package. Modified the documentation for the
urllib,urllib2 -> urllib.request,urllib.error
urlparse -> urllib.parse
RobotParser -> urllib.robotparser

Updated tutorial references and other module references (http.client.rst,
ftplib.rst,contextlib.rst)
Updated the examples in the urllib2-howto

Addresses Issue3142.
diff --git a/Doc/library/ftplib.rst b/Doc/library/ftplib.rst
index 8a35a40..f360c60 100644
--- a/Doc/library/ftplib.rst
+++ b/Doc/library/ftplib.rst
@@ -13,9 +13,9 @@
 This module defines the class :class:`FTP` and a few related items. The
 :class:`FTP` class implements the client side of the FTP protocol.  You can use
 this to write Python programs that perform a variety of automated FTP jobs, such
-as mirroring other ftp servers.  It is also used by the module :mod:`urllib` to
-handle URLs that use FTP.  For more information on FTP (File Transfer Protocol),
-see Internet :rfc:`959`.
+as mirroring other ftp servers.  It is also used by the module
+:mod:`urllib.request` to handle URLs that use FTP.  For more information on FTP
+(File Transfer Protocol), see Internet :rfc:`959`.
 
 Here's a sample session using the :mod:`ftplib` module::