Add "paste" label in new mint input

[KKA11010]

If the sole action available to the user when adding a mint is to copy and paste a mint URL, it might be beneficial to eliminate the Flotation Action Button (FAB) that initiates the add mint process.

[swedishfrenchpress]

Looks good. I think in the future we may need to revisit this and think about how we are displaying exiting mints, but it's more than good enough for now.