Instantly focus on the added property

Currently, when a user clicked on the plus button in the Properties tab to add a new property, he needs to manually click on the added property row to edit it. 
This is not user-friendly at all because the obvious next action the user would take is editing the added property. We should make QDS focus on the added property right after the plus button was clicked so that the user can instantly start pressing keys to edit the added property as he likes.