Added 'ce' to the list of "registered" values for os.name.

Make references to the posix module hyperlinks.
diff --git a/Doc/lib/libos.tex b/Doc/lib/libos.tex
index c9a4804..d150776 100644
--- a/Doc/lib/libos.tex
+++ b/Doc/lib/libos.tex
@@ -7,10 +7,10 @@
 
 This module provides a more portable way of using operating system
 (OS) dependent functionality than importing an OS dependent built-in
-module like \module{posix} or \module{nt}.
+module like \refmodule{posix} or \module{nt}.
 
 This module searches for an OS dependent built-in module like
-\module{mac} or \module{posix} and exports the same functions and data
+\module{mac} or \refmodule{posix} and exports the same functions and data
 as found there.  The design of all Python's built-in OS dependent
 modules is such that as long as the same functionality is available,
 it uses the same interface; e.g., the function
@@ -54,7 +54,7 @@
 \begin{datadesc}{name}
 The name of the OS dependent module imported.  The following names
 have currently been registered: \code{'posix'}, \code{'nt'},
-\code{'dos'}, \code{'mac'}, \code{'os2'}.
+\code{'dos'}, \code{'mac'}, \code{'os2'}, \code{'ce'}.
 \end{datadesc}
 
 \begin{datadesc}{path}