Collapse double space.

src/calibre/ebooks/metadata/sources/overdrive.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env  python2
+#!/usr/bin/env python2
 from __future__ import (unicode_literals, division, absolute_import,
                         print_function)
 

src/calibre/utils/text2int.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env  python2
+#!/usr/bin/env python2
 __author__ = "stackoverflow community"
 __docformat__ = 'restructuredtext en'
 """