Fixed misspelling of course.
Notice that script is temporarily broken.
Fix change in authentication after coursera's change.

This patch (in minor massaged form) was taken by Rogério Brito from Suresh
Jayanty's gist at <https://gist.github.com/jetume/ac8142f104c8ae70b485>.

This fixes issue #74.
Fix some whitespace.
Remove unused code for hidden videos.

They don't seem to be used anymore and we will just raise an exception in
case they happen to return.
Revert "Notice that script is temporarily broken."

This reverts commit cce2993eeb686794c7973ec481f3ec7360a047ab,
as we are not broken anymore.
Documented project's home in comment.
Acknowledge @rbrito for considerable contributions.
Don't forget to raise exceptions when we encounter unexpected situations.
Remove some type casts/coercions to str type.

This way, we try to make the code slightly more readable (which is the most
costly part of all this).
Fix erroneous indentation of the body of a loop.
Avoid creating a variable to just pass to a function.

All this is supposed to be gone when we rewrite the code to use `requests`
anyway.
Remove unused functions to make requests more explicit.

This hopefully makes the code easier to read and, potentially,
refactorable/reusable even when we rewrite using `requests`.
Update README.md

explicitly stated that email address is used in for user name
Update README.md

example showing easy updating for a list of classes
Detection of courses which appear completed.

If no lecture resource is downloaded and the last modification time to a
resource is over 30 days old, then indicate that this class is likely
completed. This is useful when maintaining a list of classes, to know
which to move out of the "current" classes being periodically updated.
Update README.md

Updates to description about Coursera.org.
Update README.md

Improved citation.
Moved the logging initialization code.
added feedback section to readme