Removing unneeded from __future__ import statements.

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

ebook_converter/ebooks/conversion/plugins/pdf_input.py

@@ -1,16 +1,14 @@
-# -*- coding: utf-8 -*-
-from __future__ import absolute_import, division, print_function, unicode_literals
-
-__license__ = 'GPL 3'
-__copyright__ = '2009, John Schember <john@nachtimwald.com>'
-__docformat__ = 'restructuredtext en'
-
 import os
 
 from ebook_converter.customize.conversion import InputFormatPlugin, OptionRecommendation
 from ebook_converter.polyglot.builtins import as_bytes, getcwd
 
 
+__license__ = 'GPL 3'
+__copyright__ = '2009, John Schember <john@nachtimwald.com>'
+__docformat__ = 'restructuredtext en'
+
+
 class PDFInput(InputFormatPlugin):
 
     name        = 'PDF Input'