Change abandoned guzzle/http to guzzle/guzzle (fixes #33)
Change abandoned guzzle/http to guzzle/guzzle (fixes #33)

Composer shows warnings in any project requiring omnipay-common, since guzzle/http is abandoned and no longer supported. This is not nice, esp. since this might introduce some security issues in future.
judgej/omnipay-common,delatbabel/omnipay-common,AndrewCarterUK/omnipay-common,incarnate/omnipay-common,delatbabel/omnipay-common,eileenmcnaughton/common,devdemon/omnipay-common,eileenmcnaughton/common,luciano-jr/omnipay-common,everpay/omnipay-common,AndrewCarterUK/omnipay-common,xola/omnipay-common,everpay/omnipay-common,luciano-jr/omnipay-common,devdemon/omnipay-common,thephpleague/omnipay-common,incarnate/omnipay-common,judgej/omnipay-common