Replace convertBaseToScreen deprecated in 10.11

Closes #534.

src/cocoa_window.m

@@ -1164,8 +1164,14 @@ void _glfwPlatformSetCursorPos(_GLFWwindow* window, double x, double y)
     }
     else
     {
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= 1070
+        const NSRect localRect = NSMakeRect(x, contentRect.size.height - y - 1, 0, 0);
+        const NSRect globalRect = [window->ns.object convertRectToScreen:localRect];
+        const NSPoint globalPoint = globalRect.origin;
+#else
         const NSPoint localPoint = NSMakePoint(x, contentRect.size.height - y - 1);
         const NSPoint globalPoint = [window->ns.object convertBaseToScreen:localPoint];
+#endif /*MAC_OS_X_VERSION_MAX_ALLOWED*/
 
         CGWarpMouseCursorPosition(CGPointMake(globalPoint.x,
                                               transformY(globalPoint.y)));