[Usability] Update name duplication feature to be easier to use

[Gear61]

1. Change the copy from "Duplicate X" to "Adjust name amount". We lose the context of the name, but the first 2 options of rename and delete have it, so we should be fine.
2. Change the duplication dialog's copy to be "How many copies of "X" do you want to have? You currently have Y copies of this name." where X is the current name and Y is the current amount. This removes the burden of doing math from the user.
3. Prefill the # of copies field with the current amount of names.
4. Keep in mind that the user might want to adjust the number down. We will need to figure out the delta (add/delete names) and call the proper APIs.
5. Change the "Add" button to say "Submit", since it won't make sense with this new copy.
6. If the user sets the # of names to be exactly the same, don't let them submit.