Added %exit, %quit and %Quit as magics for consistency.

IPython/core/magic.py

@@ -2537,6 +2537,9 b' Defaulting color scheme to \'NoColor\'"""'
 
         self.shell.ask_exit()
 
+    # Add aliases as magics so all common forms work: exit, quit, Exit, Quit.
+    magic_exit = magic_quit = magic_Quit = magic_Exit
+
     #......................................................................
     # Functions to implement unix shell-type things