### Usage
```
//init
or
import Ajax from './server.js';
//use
Ajax({
data: data, //request data
url: url, //request url
dataType: 'jsonp', //jsonp or not
type: 'get', //request method, support 'get' and 'post'
headers: {
header1: 'aaa',
header2: 'bbb'
},
success: function(json) {
console.log(json);
},
fail: function(json) {
console.log(json);
},
done: function(json) {
console.log(json);
}
});
```