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.)
diff --git a/Lib/idlelib/EditorWindow.py b/Lib/idlelib/EditorWindow.py
index 396e2bd..7cd6c1f 100644
--- a/Lib/idlelib/EditorWindow.py
+++ b/Lib/idlelib/EditorWindow.py
@@ -859,7 +859,7 @@
             try:
                 self.load_extension(name)
             except:
-                print "Failed to load extension", repr(name)
+                print("Failed to load extension", repr(name))
                 import traceback
                 traceback.print_exc()
 
@@ -870,7 +870,7 @@
         try:
             mod = __import__(name, globals(), locals(), [])
         except ImportError:
-            print "\nFailed to import extension: ", name
+            print("\nFailed to import extension: ", name)
             return
         cls = getattr(mod, name)
         keydefs = idleConf.GetExtensionBindings(name)