Guzzle 6

[chrisvanpatten]

Guzzle 4 is EOL, so it might be good to upgrade to support Guzzle 6 (and the PSR7 goodness that comes with it!)

I'm going to work on a PR to address this.

[jadb]

Hey @chrisvanpatten, have you been able to get any progress done?

I am starting to plan an upgrade as I continue using Guzzle 6 in other places but any help would be greatly appreciated.

/cc @davidchchang

[chrisvanpatten]

I stopped because the guzzle/guzzle-services and guzzle/command repos hadn't been updated with Guzzle 6 support. I think they have though, so it should be possible to update now.