Auto merge of #208 - edwin0cheng:fullscreen-mode-options, r=jdm

Add NSViewFullScreenModeOptionKey keys

This PR added NSViewFullScreenModeOptionKey values described in [here](https://developer.apple.com/documentation/appkit/nsviewfullscreenmodeoptionkey?language=objc)

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cocoa/src/appkit.rs

@@ -84,6 +84,12 @@ extern {
     // NSAppearance names. (NSString *)
     pub static NSAppearanceNameVibrantDark: id;
     pub static NSAppearanceNameVibrantLight: id;
+
+    // Fullscreen mode options - OS X v10.5 and later. (NSString *)
+    pub static NSFullScreenModeAllScreens: id;
+    pub static NSFullScreenModeSetting: id;
+    pub static NSFullScreenModeWindowLevel: id;
+    pub static NSFullScreenModeApplicationPresentationOptions: id;
 }
 
 pub const NSAppKitVersionNumber10_0: f64 = 577.0;