rename examples/tests/{a,b,c,d,e,f} into examples/acceptance_tests/00{1,2,3,4,5,6}

Also added a little Makefile to run them all in one go.

examples/acceptance_tests/006/aiken.toml

@@ -0,0 +1,2 @@
+name = "acceptance_test_006"
+version = "0.0.0"

examples/acceptance_tests/006/lib/test.ak

@@ -0,0 +1,3 @@
+test foo() {
+  (1, []) == (1, [])
+}