DOC: Add example to extract docstring, and re-explain change to match.
@jreback, I added examples per your request in #5099. Also, I rewrote the explanation of how `str.match` is changing, which I left confusing and wordy before.

Nice examples in the docstring! I added some comments related to numpy's docstring standard.

And a suggestion, while you are at it, maybe you could also add a 'See also' section to refer to `match` and `contain`?
 looks good....

lmk when you are ready for merging...
 Thanks for the help, @jorisvandenbossche . I read up on the numpy documentation standard. Ready to merge.
 @danielballan thanks...the py2.6 failure was bogus...
 @danielballan I added some more comments. Do you want to handle it a new PR (otherwise I can also do it)?
 Ah, I thought you wanted output only for the first example, for brevity. I should have asked for clarification. See #5838 .
 @danielballan yeah, maybe that wasn't very clear. But I think the examples are much more valuable to users if you can see in a glimpse the possible outputs.
