Move script context e2e tests under a nested 'v2' directory.

And rework scripts to run them in anticipation of new v3 contexts.

examples/acceptance_tests/script_context/v2/ctx/basic/tx.diag.template

@@ -0,0 +1,34 @@
+[
+    { 0:
+      [ [h'0000000000000000000000000000000000000000000000000000000000000000', 0]
+      ]
+
+    , 1:
+      [ [h'6011111111111111111111111111111111111111111111111111111111', 1000000000]
+      ]
+
+    , 2: 42
+
+    , 11: h'FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF'
+
+    , 13:
+      [ [h'0000000000000000000000000000000000000000000000000000000000000000', 0]
+      ]
+
+    , 16:
+      [ h'6000000000000000000000000000000000000000000000000000000000', 1000000000
+      ]
+
+    , 17: 1
+    },
+
+    { 5: [[0, 0, 121([]), [1000000, 100000000]]]
+
+    , 6: [h'{{ VALIDATOR }}']
+
+    },
+
+    true,
+
+    null
+]