* use system chrome instead of custom caption button on macOS
* move `BeginMoveWindow` and `MaximizeOrRestoreWindow` to `ChromelessWindow`
* better supports for fullscreen mode on macOS
* redesign the layout of title bar for all windows
Signed-off-by: leo <longshuang@msn.cn>
* move resources and styles for macOS caption button to `CaptionButtonsMacOS` because it is never used by others and should not been changed
* add `IsCloseButtonOnly` property to `CaptionButtons` and `CaptionButtonsMacOS` and replace the controls in windows
* Only allow to start interactive rebase from merged commit in current branch
* The order of commits in the interactive rebase window is as same as it's in histories page.
* Unlike anthor git frontend app `Fork`, you should edit the final message on the last commit rather than the previous commit that will be meld into while squashing commits
