Fix PyString_Format() so that '%c' % u'a' returns u'a'
instead of raising a TypeError. (From SF patch #710127)

Add tests to verify this is fixed.

Add various tests for '%c' % int.
diff --git a/Misc/NEWS b/Misc/NEWS
index 41cb887..4a0e330 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -34,6 +34,9 @@
   unicode system with multiple active interpreters, or successive
   interpreter executions, would fail.
 
+- "%c" % u"a" now returns a unicode string instead of raising a
+  TypeError. See SF patch #710127.
+
 Extension modules
 -----------------