expand tracking options and reply-to option

Please consider adding the ability to enable/disable link and open tracking. I would like to track opens, but not links. When link tracking is enabled, the replaced links are too long and appear spammy.

Please also consider adding a reply-to field to allow me to configure a reply-to on the sent emails.

I’m switching over from mandrill and their worpdress plugin provided these features and they were very helpful.