Move enabling of demandimport to dispatch.py

This avoids loading many modules before enabling demandimport.

mercurial/commands.py

@@ -5,7 +5,6 b''
 # This software may be used and distributed according to the terms
 # of the GNU General Public License, incorporated herein by reference.
 
-import demandimport; demandimport.enable()
 from node import *
 from i18n import _
 import os, re, sys, urllib

mercurial/dispatch.py

@@ -5,6 +5,7 b''
 # This software may be used and distributed according to the terms
 # of the GNU General Public License, incorporated herein by reference.
 
+import demandimport; demandimport.enable()
 from node import *
 from i18n import _
 import os, sys, atexit, signal, pdb, traceback, socket, errno, shlex, time