Fix most trivially-findable print statements.

There's one major and one minor category still unfixed:
doctests are the major category (and I hope to be able to augment the
refactoring tool to refactor bona fide doctests soon);
other code generating print statements in strings is the minor category.

(Oh, and I don't know if the compiler package works.)

Lib/lib-tk/Tkinter.py

@@ -86,7 +86,7 @@ def _cnfmerge(cnfs):
             try:
                 cnf.update(c)
             except (AttributeError, TypeError) as msg:
-                print "_cnfmerge: fallback due to:", msg
+                print("_cnfmerge: fallback due to:", msg)
                 for k, v in c.items():
                     cnf[k] = v
         return cnf