Add nodata query parameter

[petrrr]

I would like to propose that a nodata query parameter as defined by FDSNWS specification is added to the service. This would help in understand behavior especially if used in a browser window, e.g. for debugging.

[javiquinte]

I would definitely like to see this implemented. I will send an email before implementing it (in some weeks) to the ETC members to check that no one is against this, as it will require an extension of the specifications.

[Jollyfant]

I agree that it can be useful in browsers but principally I think there is a clear distinction between 204 and 404 response codes. One means success without data, and the other indicates that the resource does not exist (client error). If you need to debug just pop open the console anyway. In standardized APIs I would avoid "complexities" like this.

But I'm not against implementing this ;)