Fix capitalization

Author: ssfinney

src/MailTracking.php

@@ -53,7 +53,7 @@ public function setUpMailTracking()
     }
 
     /**
-     * Retrieve the appropriate swift message.
+     * Retrieve the appropriate Swift message.
      *
      * @param Swift_Message|null $message
      *
@@ -67,15 +67,15 @@ protected function getEmail(Swift_Message $message = null)
     }
 
     /**
-     * Retrieve the mostly recently sent swift message.
+     * Retrieve the mostly recently sent Swift message.
      */
     protected function lastEmail()
     {
         return end($this->emails);
     }
 
     /**
-     * Store a new swift message.
+     * Store a new Swift message.
      *
      * Collection of emails that were received by the MailRecorder plugin during a test.
      *