Fix #4702, make setup work on windows

system/setup

@@ -445,7 +445,7 @@ class Facts(object):
         self.facts['date_time']['minute'] = now.strftime('%M')
         self.facts['date_time']['second'] = now.strftime('%S')
         self.facts['date_time']['epoch'] = now.strftime('%s')
-        if self.facts['date_time']['epoch'][0] == '%':
+        if self.facts['date_time']['epoch'] == '' or self.facts['date_time']['epoch'][0] == '%':
             self.facts['date_time']['epoch'] = str(int(time.time()))
         self.facts['date_time']['date'] = now.strftime('%Y-%m-%d')
         self.facts['date_time']['time'] = now.strftime('%H:%M:%S')