Reformat Deskbar prefs all in one with no tabs
Implement Revert and Default buttons in Deskbar prefs
Rename 'Sort running applications' to 'Sort applications by name'
Destroy prefs window on close once again
Refactor settings so that defaults get set in 1 place.

* Move desk_settings and clock_settings struct to a new header entitled
  'BarSettings.h' so it can be included in BarApp.h and PreferencesWindow.h.
* Refactor desk_settings to only include used, or at least relevant settings,
  some cruft had built up over time.
* Refactor the InitSettings() method, all the B_OK checking wasn't working so
  I removed it. Defaults get set up to and if the corresponding setting is
  found in the settings file it is replaced, else, it is not.
* Reorder the struct and code so it goes in the order that the settings appear:
  applications, then recent items, then window settings.
* Simplify the preferences window revert and defaults code based on using the
  prebuild desk_settings structs in BarApp instead of creating our own and
  copying. All initial setup is in the constructor.
Reorder buttons.

Defaults then Revert both on left like Tracker and Locale and other preflets.
Add 'Open menu in Tracker' button at bottom
Rename Recent items back to Menu and tweak to make fit.

* Put the Open in Tracker... button back in Menu.
* Put the window checkboxes in 2 columns.
* Use vertical struts instead of insets for spacing in a couple places.
Use horizontal strut instead of insets
Save and load prefs window position to and from a file.
Reorder Default and Revert buttons in Appearance.

To match at least a couple other preflets that have Default and Revert buttons
such as Locale, CPU Frequency, Tracker, and Mouse.