- Add AlertWindow::show() and showAsync() methods that take a MessageBoxOptions argument
  - Add NativeMessageBox::show() and showAsync() methods that take a MessageBoxOptions argument
  - Update the DialogsDemo to demonstrate the new methods
  - Deprecate AlertWindow::showNativeDialogBox() in favour of the NativeMessageBox methods
  - Pass button strings specified in MesssageBoxOptions to native dialog boxes correctly
  - Use modern TaskDialog on Windows for the native dialog box where available

See BREAKING-CHANGES.txt for more details.

When bridging 32-bit/64-bit plugins on Windows, the plugin is hosted in
an auxilliary process, and the plugin's editor is embedded into an HWND
owned by a different process (the plugin host).

Previously, the `isForegroundProcess` check would fail for bridged
plugins, because the foreground window may belong to the DAW, rather
than to the auxilliary hosting process.

This patch adds an additional check, to find whether the same process
owns both the foreground window, and the window which embeds the
PopupMenu's target component. In this case, we avoid immediately
dismissing the PopupMenu.

This fixes warnings that are emitted when building with the `-analyze`
flag enabled.

For DialogWindow, uses the scale of componentToCentreAround.

This allows drawing dialog windows at the expected scale in plugins.
An associated component must be supplied in order for this to work.