leap: Update test cases (#441)

Adds the changes made to the the canonical test data in
exercism/problem-specifications#463
and stores the test data version.

Author: behrtam

exercises/leap/leap_test.py

@@ -3,21 +3,20 @@
 from leap import is_leap_year
 
 
-class YearTest(unittest.TestCase):
-    def test_leap_year(self):
-        self.assertIs(is_leap_year(1996), True)
+# test cases adapted from `x-common//canonical-data.json` @ version: 1.0.0
 
-    def test_non_leap_year(self):
-        self.assertIs(is_leap_year(1997), False)
+class YearTest(unittest.TestCase):
+    def test_year_not_divisible_by_4(self):
+        self.assertFalse(is_leap_year(2015))
 
-    def test_non_leap_even_year(self):
-        self.assertIs(is_leap_year(1998), False)
+    def test_year_divisible_by_4_not_divisible_by_100(self):
+        self.assertTrue(is_leap_year(2016))
 
-    def test_century(self):
-        self.assertIs(is_leap_year(1900), False)
+    def test_year_divisible_by_100_not_divisible_by_400(self):
+        self.assertFalse(is_leap_year(2100))
 
-    def test_exceptional_century(self):
-        self.assertIs(is_leap_year(2400), True)
+    def test_year_divisible_by_400(self):
+        self.assertTrue(is_leap_year(2000))
 
 
 if __name__ == '__main__':