add query json plugin for experimentation (#3327)

* add query json plugin for experimentation

* add some error handling

* closer but Kind::Array is still horked

* unravel the table so the output looks right

* clippy

* added the ability to use gjson modifiers

src/plugins/nu_plugin_extra_query_json.rs

@@ -0,0 +1,6 @@
+use nu_plugin::serve_plugin;
+use nu_plugin_query_json::QueryJson;
+
+fn main() {
+    serve_plugin(&mut QueryJson::new());
+}