Crawler for Valor Econômico and ZH

[veniciusgrjr]

I fixed the problem related to line breaking, to the new style string formatting, to print statements and to unnecessary imports, as suggested for @flavioamieiro.
I also created a crawler for ZH.
Please, take a look at these codes.

[fccoelho]

@veniciusgrjr it is good style to end files with a new linecharacter. can you please fix this?
if you are curious why, read this: http://unix.stackexchange.com/questions/18743/whats-the-point-in-adding-a-new-line-to-the-end-of-a-file

[fccoelho]

We need tests for these crawlers. @veniciusgrjr, are you familiar with unit testing in Python?

[flavioamieiro]

Just for the sake of style I'd remove this space before the close parenthesis. (Also on the line, in the BeautifulSoup instantiation and in some other places bellow).

[flavioamieiro]

I think the original issues are covered (except for adding the newline at the end of files, please do that).

I agree with @fccoelho that it would be great to have unit tests for these. If we can do that, we should.

[veniciusgrjr]

I fixed de problems related to new linecharacter at the end of the files and to some unnecessary spaces.
I'm working on the unity tests.