更新前端静态网页获取方式，放弃使用后端获取api

frontend/node_modules/static-eval/example/vars.js

@@ -0,0 +1,11 @@
+var evaluate = require('../');
+var parse = require('esprima').parse;
+
+var src = '[1,2,3+4*10+n,foo(3+5),obj[""+"x"].y]';
+var ast = parse(src).body[0].expression;
+
+console.log(evaluate(ast, {
+    n: 6,
+    foo: function (x) { return x * 100 },
+    obj: { x: { y: 555 } }
+}));