My first PR ever.  Adding documentation to Cookbook.
Just adding some more description to Cookbook documentation per J. Reback's request.  If I didn't mess up anything here, I will go through the rest of the items and add some description.

Please let me know if I messed anything up.

Hi!  very glad to be on the receiving side of your very first PR.

The first commit solves a problem that I'm not sure exists, and it basically rewrites the entire file,
although I don't see any dangling whitespace in it.
if you're on windows, it's possible that your git repo is setup to automatically
convert line endings.
 Hi y-p,  

Thanks for the feedback.  I noticed that most of the other `.rst` docs did not have the line ending characters from a file created on Windows*.  When cookbook.rst was first created, I'm guessing the line endings were not handled by git.

I removed all `^M` 's just to make it cleaner for editing because I wasn't sure if mixing the line endings might have unwanted side effects.

Let me know what you think...but I'm happy to change it back.  

*http://stackoverflow.com/questions/5843495/what-does-m-character-mean-in-vim
 Thanks, had to resort to hexdump to realize the problem. I rewrote the file
for line endings as @jreback, and incorporated your additions. Thanks for the PR.

aside, consider setting up you git email to a real address using `git config`,
and try to avoid introducing dangling whitespace into patches, your editor
might have a tweakable for that.
 I will make those changes accordingly!  I intend to complete documentation in the cookbook in my next PR.
