tools/update_revnum.py now gives path (req for some svn version)

tools/update_revnum.py

@@ -3,11 +3,11 b''
 import os
 import re
 
-rev = os.popen('svnversion').read().strip()
+rev = os.popen('svnversion ..').read().strip()
 
 print "current rev is",rev
 assert ':' not in rev
 
 rfile = open('../IPython/Release.py').read()
 newcont = re.sub(r'revision\s*=.*', "revision = '%s'" % rev, rfile)
-open('../IPython/Release.py','w').write(newcont)
  No newline at end of file
+open('../IPython/Release.py','w').write(newcont)