[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/package.json

@@ -0,0 +1,19 @@
+{
+  "name": "paddlejs-demo",
+  "version": "0.0.1",
+  "description": "",
+  "main": "app.js",
+  "dependencies": {
+    "@paddlejs/paddlejs-backend-webgl": "^1.2.0",
+    "@paddlejs/paddlejs-core": "^2.1.18",
+    "d3-polygon": "2.0.0",
+    "js-clipper": "1.0.1",
+    "number-precision": "1.5.2"
+  },
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC"
+}