Fixed issue with comparing against None

Thanks to github user sidahmed-malaoui for the bug report

crontab/_crontab.py

diff --git a/crontab/_crontab.py b/crontab/_crontab.py
index 9a1cce9..fd7f0ca 100644
--- a/crontab/_crontab.py
+++ b/crontab/_crontab.py
@@ -3,7 +3,7 @@
 crontab.py
 
 Written July 15, 2011 by Josiah Carlson
-Copyright 2011-2018 Josiah Carlson
+Copyright 2011-2020 Josiah Carlson
 Released under the GNU LGPL v2.1 and v3
 available:
 http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
@@ -386,6 +386,8 @@
         self.matchers = self._make_matchers(crontab, loop, random_seconds)
 
     def __eq__(self, other):
+        if not isinstance(other, CronTab):
+            return False
         match_last = self.matchers[1:] == other.matchers[1:]
         return match_last and ((self.rs and other.rs) or (not self.rs and
             not other.rs and self.matchers[0] == other.matchers[0]))

setup.py

diff --git a/setup.py b/setup.py
index 814cd9c..0a8e6e4 100644
--- a/setup.py
+++ b/setup.py
@@ -10,7 +10,7 @@
 
 setup(
     name='crontab',
-    version='0.22.8',
+    version='0.22.9',
     description='Parse and use crontab schedules in Python',
     author='Josiah Carlson',
     author_email='josiah.carlson@gmail.com',