Implement -[NSViewController view{Will|Did}{Appear|Disappear}]

Author: ethanc8

Headers/AppKit/NSViewController.h

@@ -96,7 +96,12 @@ APPKIT_EXPORT_CLASS
 - (void) viewDidAppear: (BOOL)animated;
 - (void) viewWillDisappear: (BOOL)animated;
 - (void) viewDidDisappear: (BOOL)animated;
-
+#if OS_API_VERSION(MAC_OS_X_VERSION_10_10, GS_API_LATEST)
+- (void) viewWillAppear;
+- (void) viewDidAppear;
+- (void) viewWillDisappear;
+- (void) viewDidDisappear;
+#endif
 #if OS_API_VERSION(MAC_OS_X_VERSION_10_10, GS_API_LATEST)
 - (void) dismissViewController: (NSViewController *)viewController;
 - (void) dismissController: (id)sender;

Source/NSViewController.m

@@ -83,6 +83,7 @@ - (void)viewDidLoad
 
 - (void) viewWillAppear: (BOOL)animated
 {
+  [self viewWillAppear];
 }
 
 - (void) viewIsAppearing: (BOOL)animated
@@ -91,13 +92,32 @@ - (void) viewIsAppearing: (BOOL)animated
 
 - (void) viewDidAppear: (BOOL)animated
 {
+  [self viewDidAppear];
 }
 
 - (void) viewWillDisappear: (BOOL)animated
 {
+  [self viewWillDisappear];
 }
 
 - (void) viewDidDisappear: (BOOL)animated
+{
+  [self viewDidDisappear];
+}
+
+- (void) viewWillAppear
+{
+}
+
+- (void) viewWillDisappear
+{
+}
+
+- (void) viewDidAppear
+{
+}
+
+- (void) viewDidDisappear
 {
 }