How to mark as read e-mails from a certain person in mail app
Using the "Rules" feature of Mail in Yosemite, you can make it so emails from a certain address are automatically marked as read by following these steps:


Open Preferences (CMD + , or Preferences in the Mail Menu)
Navigate to the Rules Tab (furthest to the right)
"Add Rule"
Condition: "From" "is equal to" "(email goes here)"
Action: "Mark as Read"