[Model] add Paddle.js web demo (#392)

* add application include paddle.js web demo and xcx

* cp PR #5

* add readme

* fix comments and link

* fix xcx readme

* fix Task 1

* fix bugs

* refine readme

* delete ocrxcx readme

* refine readme

* fix bugs

* delete old readme

* 200px to 300px

* revert 200px to 300px

Co-authored-by: Jason <jiangjiajun@baidu.com>

examples/application/js/mini_program/ocrdetectXcx/app.js

@@ -0,0 +1,12 @@
+/* global wx, App */
+import * as paddlejs from '@paddlejs/paddlejs-core';
+import '@paddlejs/paddlejs-backend-webgl';
+// eslint-disable-next-line no-undef
+const plugin = requirePlugin('paddlejs-plugin');
+plugin.register(paddlejs, wx);
+
+App({
+    globalData: {
+        Paddlejs: paddlejs.Runner
+    }
+});