Composer autoloading issue

[drakakisgeo]

Hi there,
I get this error when I run composer dumpautoload

Class Postmark\InboundException located in ./vendor/jjaffeux/postmark-inbound-php/lib/Postmark/Exception.php does not comply with psr-0 autoloading standard. Skipping.

I am using "jjaffeux/postmark-inbound-php": "^3.0",

[navitronic]

Have created a PR to fix this: #16