Some updates which maybe help someone

Easy way to change an image with a preferred tool
Just need to add 'manipulateImage' function to the settings helper which receives 
the result of reader.readAsDataURL and should run the uploadCallback 
with the result dataUrl 

```javascript
manipulateImage: function(imageDataUrl, fileData, uploadCallback) {
  img = new Image()
  img.onload = function() {

    Caman(this, function() {
      this.resize({
        height: 100
      })

      this.render(function() {
        uploadCallback(this.canvas.toDataURL(fileData.type))
      })

    });
  }

  img.src = imageDataUrl

}

```
Way to restrict uploads on the client side, just to prevent to upload pdf where image should be
also configurable inside of settings helper.

```javascript
accept: "image/*",
```

Show result fileName inside of onUpload, to not to save a full url because it's too long,
but just a file name