tests/basics: Add test for logical constant folding.

tests/basics/logic_constfolding.py

+# tests logical constant folding in parser
+
+def f_true():
+    print('f_true')
+    return True
+
+def f_false():
+    print('f_false')
+    return False
+
+print(0 or False)
+print(1 or foo)
+print(f_false() or 1 or foo)
+print(f_false() or 1 or f_true())
+
+print(0 and foo)
+print(1 and True)
+print(f_true() and 0 and foo)
+print(f_true() and 1 and f_false())
+
+print(not 0)
+print(not False)
+print(not 1)
+print(not True)
+print(not not 0)
+print(not not 1)