canonic(): Fix by Edward K Ream to make breakpoints work better on

Windows: apply normcase() as well as abspath().  (Note: this isn't
needed to make IDLE work, but it's a good idea anyway.)

Bugfix candidate -- both 2.2.1 and 2.1.3.

Lib/bdb.py

@@ -28,6 +28,7 @@ def canonic(self, filename):
         canonic = self.fncache.get(filename)
         if not canonic:
             canonic = os.path.abspath(filename)
+            canonic = os.path.normcase(canonic)
             self.fncache[filename] = canonic
         return canonic