Add customizable names to filter presets

[mjdescy]

Allowing the user to name filter presets and to display the name of the filter preset in the status bar would be very helpful.

I decided long ago that showing the filters as strings in the status bar (or elsewhere in the UI) would not work. They would be too cryptic. I never thought to allow users to customize the filter names until now, however.

I will implement this as soon as I am able to get Xcode to stop crashing in Interface Builder mode. Xcode 7.2 is completely unusable when adjusting the layout of the Filters window for this application.