Refactor to move parseConfiguration function into a separate file, add stronger typing, add first test case.

test/parse-configuration-test.mjs

@@ -0,0 +1,24 @@
+// @ts-check
+
+import test from "ava";
+import parseConfiguration from "../lib/parse-configuration.mjs";
+
+const testObject = {
+  "string": "text",
+  "number": 10,
+  "object": {
+    "property": "value"
+  },
+  "array": [ 1, 2, 3 ]
+};
+const successfulTestObjectResult = {
+  "config": testObject,
+  "message": ""
+};
+const testObjectJsonString = JSON.stringify(testObject);
+
+test("json object, default parsers", (t) => {
+  t.plan(1);
+  const actual = parseConfiguration("name", testObjectJsonString);
+  t.deepEqual(actual, successfulTestObjectResult);
+});