Support for Project level settings

[diegoroccia]

Is your enhancement related to a problem?

No

Describe the solution you would like

the ability to provide project settings, for example schema mappings

Describe alternatives you have considered

I have my configuration in the editor that takes care of this, but in my team there is not a single editor, so this is not going to scale

Additional context

This was already suggested in #68 but the idea was dropped. Since it was 7 years ago, I thought it may be reconsidered, since most language servers support this