Added JSONFormatter interface and tests

jsoneditoronline/jsoneditoronline-tests.ts

@@ -16,4 +16,20 @@ var json:JSON = {
 editor.set(json);
 editor.expandAll();
 
-var json2:JSON = editor.get(json);
+var jsonResult:JSON = editor.get(json);
+
+var options2: JSONformatterOptions = {
+    "indentation": 2
+};
+var formatter:JSONFormatter = new JSONFormatter(container, options);
+var json2:JSON = {
+    "Array": [1, 2, 3],
+    "Boolean": true, 
+    "Null": null, 
+    "Number": 123, 
+    "Object": {"a": "b", "c": "d"},
+    "String": "Hello World"
+};
+formatter.set(json2);
+
+var jsonResult2:JSON = formatter.get(json2);

jsoneditoronline/jsoneditoronline.d.ts

@@ -29,4 +29,9 @@ interface JSONFormatterOptions {
 
 interface JSONFormatter {
 	(container:HTMLElement, options?: JSONFormatterOptions, json?: JSON): JSONEditor;
+	(container:HTMLElement, options?: JSONFormatterOptions, json?: string): JSONEditor;
+	set(json: JSON);
+	get(): JSON;
+	setText(jsonString: string);
+	getText(): string;
 }