Cleanup/harmonize whitespace

Leading indent should consist only of tabs, beyond that, only spaces should be used.
Parse the ‘required’ field from remote bundle index
Move version comparison out of s/w update framework
Improve “Open With” submenu

- Path to application is shown in the menu item’s tool tip.
- When menu is shown for multiple file types with different default applications, we show the default applications first.
- Use the potentially localized bundle name rather than file system display name.
- Use bundle identifier to group applications rather than display name: Grouping is done to decide if version number should be shown for the item.
Use NSWindow’s stringWithSavedFrame instead of window.frame

This includes the screen dimension so that restoring the frame on a different screen can scale the window accordingly.