Add Message.
Require guzzlehttp/guzzle:~4.
Exclude Tests/ from code coverage.
Require Composer libraries to support PHP 5.4.
Add MessagingService.
Test Message.
Reorganise use statements.
Test delivery information missing, unknown status codes.
Make API exceptions implement ApiException to expose errors.
Add Bundle configuration.
Add service definitions.
Fix indentation.
Create wrapper messaging service.
Exclude tests from PHPMD checks.
Exclude PHP 5.3 from builds.
Add test to expand ApiRuntimeException code coverage.
Ignore code coverage for bundle Configuration.
Adjust Scrutinizer code style checks.
Describe installation process
Describe messaging service usage