Add 'osx' as a command-line option for --gui=.

IPython/core/magics/basic.py

@@ -410,7 +410,7 b' Defaulting color scheme to \'NoColor\'"""'
             %gui gtk     # enable PyGTK event loop integration
             %gui gtk3    # enable Gtk3 event loop integration
             %gui tk      # enable Tk event loop integration
-            %gui OSX     # enable Cocoa event loop integration
+            %gui osx     # enable Cocoa event loop integration
                          # (requires %matplotlib 1.1)
             %gui         # disable all event loop integration
 

IPython/core/shellapp.py

@@ -165,8 +165,8 b' class InteractiveShellApp(Configurable):'
     module_to_run = Unicode('', config=True,
         help="Run the module as a script."
     )
-    gui = CaselessStrEnum(('qt', 'wx', 'gtk', 'glut', 'pyglet'), config=True,
-        help="Enable GUI event loop integration ('qt', 'wx', 'gtk', 'glut', 'pyglet')."
+    gui = CaselessStrEnum(('qt', 'wx', 'gtk', 'glut', 'pyglet', 'osx'), config=True,
+        help="Enable GUI event loop integration ('qt', 'wx', 'gtk', 'glut', 'pyglet', 'osx')."
     )
     pylab = CaselessStrEnum(['tk', 'qt', 'wx', 'gtk', 'osx', 'inline', 'auto'],
         config=True,