Force __toString from Guzzle\Http\EntityBody Object

without (string) wo won´t see any response xml
Merge pull request #3 from michabbb/develop

Force __toString from Guzzle\Http\EntityBody Object
refactor: make Guzzle client a return string

Response from Guzzle client is an instance of
Guzzle\Http\EntityBodyInterface. Pass true to getBody to return a string
instead.
Merge branch 'guzzle' into develop
doc: update CHANGELOG
Merge branch 'changelog' into develop
release: 0.0.7
Merge branch 'release-0.0.7'