QuakeML output for all cases

[claudiodsf]

This is a follow-up of the discussion started in #29.

It would be nice to be able to generate QuakeML in all cases, even if there is no QuakeML output.
Also, QuakeML output should be an option.

This will take quite some work, since we need to create an ObsPy Event() object (including location and picks) from scratch for cases when we don't have a QuakeML (parsed to Event() by ObsPy) as input.

So, I will leave it here for after releasing v1.7.

@krisvanneste, I would like to know if that's a feature you need, or it's just something that would be nice to have.

[krisvanneste]

I don't personally need this, it just seemed awkward compared to the other output options.

On the other hand, if you implement it, it would probably be best to do it at the beginning of the process flow. It could for instance eliminate the need for custom Pick and Hypo objects in ssp_read_event_metadata.py.

I have partly implemented creation of obspy Event and Pick objects, which may provide a good starting point:

• https://gitlab-as.oma.be/kris/eqcatalog/-/blob/master/eqrecord.py#L1232
• https://gitlab-as.oma.be/kris/robspy/-/blob/master/phase_pick.py#L194

[claudiodsf]

Yes, good idea.

I'll look into that after releasing v1.7 😉