add ClientBuilder->setConnectionParams()

[Oliboy50]

Closes #382

We want to be able to pass ['client'][] options globally instead of "per request".

This is the PR for the master branch, see #506 for 2.x branch.

Other related issues: #259

[johntiror]

Hi, I couldn't find documentation regarding this new method. How can I set the timeout? like this?
$params['client']['timeout']=10;

Thanks

[polyfractal]

@johntiror Yep!

There's also $params['client']['connect_timeout'] which controls the original connection timeout duration ('timeout' controls the request timeout, not the initial connection). Most folks don't really care which, but sometimes the distinction matters :)