Remove updating of revnumber in final tarball.

This makes the released code be different from the backup.  Instead, the
release manager must at the end, do a final update_revnum and commit prior
to release, so that the publicly available code matches the static backup.

tools/make_tarball.py

@@ -8,8 +8,6 b' import shutil'
 
 from  toollib import *
 
-c('python update_revnum.py')
-
 execfile('../IPython/Release.py')  # defines version_base
 
 ver = version_info()