Removing unneeded from __future__ import statements.

Since we are on Python 3.6 and up, we don't need those anymore.

ebook_converter/customize/profiles.py

@@ -1,12 +1,10 @@
-# vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
-from __future__ import absolute_import, division, print_function, unicode_literals
+from ebook_converter.customize import Plugin as _Plugin
+from ebook_converter.polyglot.builtins import zip
+
 __license__ = 'GPL 3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
-from ebook_converter.customize import Plugin as _Plugin
-from ebook_converter.polyglot.builtins import zip
-
 FONT_SIZES = [('xx-small', 1),
               ('x-small',  None),
               ('small',    2),