Initial commit: Developer Tools MVP with visual editor

- Complete React app with 7 developer tools
- JSON Tool with visual structured editor
- Serialize Tool with visual structured editor
- URL, Base64, CSV/JSON, Beautifier, Diff tools
- Responsive navigation with dropdown menu
- Dark/light mode toggle
- Mobile-responsive design with sticky header
- All tools working with copy/paste functionality

node_modules/bluebird/js/release/nodeify.js

@@ -0,0 +1,58 @@
+"use strict";
+module.exports = function(Promise) {
+var util = require("./util");
+var async = Promise._async;
+var tryCatch = util.tryCatch;
+var errorObj = util.errorObj;
+
+function spreadAdapter(val, nodeback) {
+    var promise = this;
+    if (!util.isArray(val)) return successAdapter.call(promise, val, nodeback);
+    var ret =
+        tryCatch(nodeback).apply(promise._boundValue(), [null].concat(val));
+    if (ret === errorObj) {
+        async.throwLater(ret.e);
+    }
+}
+
+function successAdapter(val, nodeback) {
+    var promise = this;
+    var receiver = promise._boundValue();
+    var ret = val === undefined
+        ? tryCatch(nodeback).call(receiver, null)
+        : tryCatch(nodeback).call(receiver, null, val);
+    if (ret === errorObj) {
+        async.throwLater(ret.e);
+    }
+}
+function errorAdapter(reason, nodeback) {
+    var promise = this;
+    if (!reason) {
+        var newReason = new Error(reason + "");
+        newReason.cause = reason;
+        reason = newReason;
+    }
+    var ret = tryCatch(nodeback).call(promise._boundValue(), reason);
+    if (ret === errorObj) {
+        async.throwLater(ret.e);
+    }
+}
+
+Promise.prototype.asCallback = Promise.prototype.nodeify = function (nodeback,
+                                                                     options) {
+    if (typeof nodeback == "function") {
+        var adapter = successAdapter;
+        if (options !== undefined && Object(options).spread) {
+            adapter = spreadAdapter;
+        }
+        this._then(
+            adapter,
+            errorAdapter,
+            undefined,
+            this,
+            nodeback
+        );
+    }
+    return this;
+};
+};