Log Message:
Update to 0.7.1:
* Changed File menu to Key menu
* Added context menu for keys
* Added buttons/menu items for possible, but not-yet-implemented features
* Sign an entire key
* Add a revoker to a key
* Bug fix when setting Ascii Armor Preferences
* Removed File Manager, replaced with file operations in Tools
* Key pairs initially listed first
* Performance improvements with large key rings, especially in loading
  preferences
* Progress display at startup for listing of keys
* Can delete subkeys of non key-pairs
* General interface cleanups