[2.7] bpo-30380: Fix Sphinx 1.6.1 warnings. (GH-1613) (#1616)

* Use explicit numbering for footnotes referred by explicit number.
* Fix literal strings formatting in howto/urllib2.rst.
* Add `:noindex:` to duplicated definition of list.
* Update susp-ignored.csv for reference/expressions.rst.
(cherry picked from commit d97b7dc94b19063f0589d401bdc4aaadc7030762)
diff --git a/Doc/library/functions.rst b/Doc/library/functions.rst
index c1ce258..c82a897 100644
--- a/Doc/library/functions.rst
+++ b/Doc/library/functions.rst
@@ -741,6 +741,7 @@
 
 
 .. class:: list([iterable])
+   :noindex:
 
    Return a list whose items are the same and in the same order as *iterable*'s
    items.  *iterable* may be either a sequence, a container that supports