Add uam/postmark-swiftmailer-bundle
Use just   = ->get('postmark.message');
Add mlpz/postmark-bundle, egulias/email-validator
Add Model\Postmark\Response
Add service wrapper around sending via postmark; will allow mockery in tests
Switch to postmark http api, no more swiftmailer w/smtp
Updated dist app params; added encrypted postmark params for CI