Fix invalid types, null pointer use, memory leak

Closes #612.

src/cocoa_window.m

@@ -739,6 +739,7 @@ static void createMenuBar(void)
     [[appMenu addItemWithTitle:@"Services"
                        action:NULL
                 keyEquivalent:@""] setSubmenu:servicesMenu];
+    [servicesMenu release];
     [appMenu addItem:[NSMenuItem separatorItem]];
     [appMenu addItemWithTitle:[NSString stringWithFormat:@"Hide %@", appName]
                        action:@selector(hide:)
@@ -757,6 +758,7 @@ static void createMenuBar(void)
 
     NSMenuItem* windowMenuItem =
         [bar addItemWithTitle:@"" action:NULL keyEquivalent:@""];
+    [bar release];
     NSMenu* windowMenu = [[NSMenu alloc] initWithTitle:@"Window"];
     [NSApp setWindowsMenu:windowMenu];
     [windowMenuItem setSubmenu:windowMenu];