revised by R. David Murray.

Before, if a default was set on the parent parser, any default for that
variable set via set_defaults on a subparser would be ignored.  Now
the subparser set_defaults is honored.

Patch by Jyrki Pullianinen.

when compiled with VS 2010 or above.  Initial patch by Tabrez Mohammed.

htests to add # htest # marker for coveragepy and stop tcl errors.

Move test lines up with respect to icons.

a filename, pop up the Open Module box. If a module is opened, open a
corresponding browser.

easily recognize and display boolean values as such and recognize changes.
Also reformat comments and alphabetize extensions included with Idle.

Thanks to Ezio for noticing this

.message is not an essential part of the test.

Patch by Meador Inge.

This gets rid of  Tcl warnings when they are handled later when the root is
already destroyed.

Patch by Chris Jerdonek.

Patch by David Naylor.

In particular, correctly describe the behavior of ntpath.join.

Based on a patch by Dave Sawyer.