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/mint/tx.diag.template

@@ -0,0 +1,25 @@
+[
+    { 0:
+      [ [h'0000000000000000000000000000000000000000000000000000000000000000', 0]
+      ]
+
+    , 1:
+      []
+
+    , 2: 1
+
+    , 9:
+      { h'{{ VALIDATOR_HASH }}': { h'666f6f': 1337 }
+      }
+    },
+
+    { 5: [[1, 0, 121([]), [1000000, 100000000]]]
+
+    , 6: [h'{{ VALIDATOR }}']
+
+    },
+
+    true,
+
+    null
+]