Fix UTC timezone test case if pytz not available; add tests

UTC is a special known timezone so it doesn't raise an exception even
if pytz is missing.

Added test case with bogus timezone that raises exception. Added
testcase for EST that is known with and without pytz.

Author: rouilj

test/test_config.py

@@ -112,13 +112,23 @@ def testTimeZone(self):
                     config._get_option('TIMEZONE').set("UTC"))
             self.assertEqual(None,
                     config._get_option('TIMEZONE').set("America/New_York"))
+            self.assertEqual(None,
+                    config._get_option('TIMEZONE').set("EST"))
+            self.assertRaises(configuration.OptionValueError,
+                    config._get_option('TIMEZONE').set, "Zool/Zot")
 
         except ImportError:
-            self.assertRaises(configuration.OptionValueError,
-                    config._get_option('TIMEZONE').set, "UTC")
+            # UTC is a known offset of 0 coded into roundup.date
+            # so it works even without pytz.
+            self.assertEqual(None,
+                    config._get_option('TIMEZONE').set("UTC"))
+            # same with EST known timeone offset of 5
+            self.assertEqual(None,
+                    config._get_option('TIMEZONE').set("EST"))
             self.assertRaises(configuration.OptionValueError,
                     config._get_option('TIMEZONE').set, "America/New_York")
 
+
     def testWebSecretKey(self):
         config = configuration.CoreConfig()