Add option to configure the server url
In order to use this with 3rd party server side tracking services such as stape, we need the ability to configure the server url. I've added this option.
Even if the code looks good, I don't think it will be merged due to the status of the repo. You could instead use the npm package by @darjama, which already includes the changes you need. Or alternatively the package from us which contains the change as well as other open pull requests from here.
Please note that both packages let you overwrite the whole script URL. This allows you to use the Custom Script loader feature of stape to mask certain scripts.
PS: if you are dissatisfied with stape, you can also try our service at sooro.io. 😎