make it possible to customize widget

[shalakhin]

@and3rson haven't checked yet but it seems that it is not supporting attrs that other widgets have.

It would be very helpful I think

[and3rson]

Hey!
Sorry for the huge delay. I've recently been busy with a lot of other stuff.
The project is currently looking for maintainers.
Please open a issue if you are willing to contribute some time to this.
Thanks!