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
diff --git a/main.py b/main.py
index 10e1cf8..14a5761 100755
--- a/main.py
+++ b/main.py
@@ -87,7 +87,7 @@
     name = None
     glob = []
 
-    for i in xrange(0, len(argv)):
+    for i in range(len(argv)):
       if not argv[i].startswith('-'):
         name = argv[i]
         if i > 0: