Add test for slot function.

tests/TestCadQuery.py

@@ -2059,3 +2059,17 @@ class TestCadQuery(BaseTest):
         s = r.findSolid()
         self.assertEqual(len(s.Solids()),2)
         self.assertTrue(isinstance(s,Compound))
+
+    def testSlot(self):
+
+        decimal_places = 9
+
+        #Ensure it produces a solid with the correct volume
+        result = Workplane("XY").slot(4,1,0).extrude(1)
+        self.assertAlmostEqual(result.val().Volume(), 3.785398163)
+
+        #Test to see if slot is rotated correctly
+        result = Workplane("XY").slot(4,1,45).extrude(1)
+        point = result.faces(">Z").edges(">X").first().val().startPoint().toTuple()
+        self.assertTupleAlmostEquals(point, (0.707106781, 1.414213562, 1.0), decimal_places)
+