Update README.rst
minor #164 [RFC] Update README.rst for Guzzle 4 cURL options (jcroll)

This PR was merged into the 2.0-dev branch.

Discussion
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[RFC] Update README.rst for Guzzle 4 cURL options

Please see:

https://github.com/fabpot/Goutte/issues/69

https://github.com/fabpot/Goutte/pull/162

Commits
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ed80a44 Update README.rst