Spelling fixes supplied by Rob W. W. Hooft. All these are fixes in either
comments, docstrings or error messages. I fixed two minor things in
test_winreg.py ("didn't" -> "Didn't" and "Didnt" -> "Didn't").

There is a minor style issue involved: Guido seems to have preferred English
grammar (behaviour, honour) in a couple places. This patch changes that to
American, which is the more prominent style in the source. I prefer English
myself, so if English is preferred, I'd be happy to supply a patch myself ;)
diff --git a/Objects/intobject.c b/Objects/intobject.c
index 022c298..20bb370 100644
--- a/Objects/intobject.c
+++ b/Objects/intobject.c
@@ -311,7 +311,7 @@
 /*
 Integer overflow checking used to be done using a double, but on 64
 bit machines (where both long and double are 64 bit) this fails
-because the double doesn't have enouvg precision.  John Tromp suggests
+because the double doesn't have enough precision.  John Tromp suggests
 the following algorithm:
 
 Suppose again we normalize a and b to be nonnegative.