Change usages of xrange() to range()

In Python3, range() creates a generator rather than a list.

None of the parameters in the ranges changed looked large enough
to create an impact in memory in Python2.  Note: the only use of
range() was for iteration and did not need to be changed.

This is part of a series of changes to introduce Python3 support.

Change-Id: I50b665f9296ea160a5076c71f36a65f76e47029f

repo

@@ -606,7 +606,7 @@ def _ParseArguments(args):
   opt = _Options()
   arg = []
 
-  for i in xrange(0, len(args)):
+  for i in range(len(args)):
     a = args[i]
     if a == '-h' or a == '--help':
       opt.help = True