Add note about the future of the Indexed module.

Signed-off-by: Austin Seipp <mad.one@gmail.com>
Add a traditional callCC operator.

This operator was also initially written in terms of shift by
Leon P Smith, who is awesome. Note: I only believe the code to
work, I have not tried it (I'm no Knuth, either.)

I will probably use this in the tutorial.

Signed-off-by: Austin Seipp <mad.one@gmail.com>
Overhaul tutorial structure a bit.

I think this new structure will serve a bit better. It's inspired
(roughly) by the layout for the CC-delcont tutorial, written by Dan
Doel (see link in .Tutorial module.)

Signed-off-by: Austin Seipp <mad.one@gmail.com>
Specify missing modules in doctests.

Signed-off-by: Austin Seipp <mad.one@gmail.com>
Reorganize tutorial, inline Tree example I want to use.

Signed-off-by: Austin Seipp <mad.one@gmail.com>
Add Iterator example, based on Dan Doel's CC-delcont example

Signed-off-by: Austin Seipp <mad.one@gmail.com>
Add Leon to the Copyright since he's technically part author!

Signed-off-by: Austin Seipp <mad.one@gmail.com>