Fixed the off-by-two error in the displays pop-ups on the Applications tab (#251376).

Among the changes:
1. We no longer use Bindings to populate the pop-up menus. Instead, we populate them ourselves.
2. Likewise, we no longer use Bindings to set the pop-up menus' selections, and the pop-up menus do not talk directly to the relevant array controllers. Instead, the pop-ups send action messages to the preference pane, and each action method changes the application's or notification's display setting.
3. The Configure button and table view double-click action now both go through the same method.
4. The action method for activating the Applications tab (see #3) repopulates the displays pop-ups and updates their selections.
5. We now identify the selected display by its bundle name (in the representedObject property of the menu item), instead of by its index.

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">

<plist version="1.0">

<dict>

	<key>IBFramework Version</key>

	<string>672</string>

	<key>IBLastKnownRelativeProjectPath</key>

	<string>../../../Growl.xcodeproj</string>

	<key>IBOldestOS</key>

	<integer>5</integer>

	<key>IBOpenObjects</key>

	<array>

		<integer>12</integer>

	</array>

	<key>IBSystem Version</key>

	<string>9F33</string>

	<key>targetFramework</key>

	<string>IBCocoaFramework</string>

</dict>

</plist>