Fix a bunch of typos in documentation, docstrings and comments.
(From SF patch #810751)
diff --git a/Doc/whatsnew/whatsnew20.tex b/Doc/whatsnew/whatsnew20.tex
index 86d54d7..1728e1a 100644
--- a/Doc/whatsnew/whatsnew20.tex
+++ b/Doc/whatsnew/whatsnew20.tex
@@ -1000,7 +1000,7 @@
\method{characters()} method is called for every chunk of character
data, and so forth.
-The advantage of the event-driven approach is that that the whole
+The advantage of the event-driven approach is that the whole
document doesn't have to be resident in memory at any one time, which
matters if you are processing really huge documents. However, writing
the SAX handler class can get very complicated if you're trying to