Enhancement: support for multiple alias fields

[nousernameavailableanymore]

The alias_field feature is great.
It would be awesome if multiple fields could be shown in the query results.

I have meeting notes which include the date, reason and participants.
Ideally all of those fields could returned in the query results.
The filename is usually not that interesting when proper YAML metadata is available.
So only having one alias is a bit limiting 🙂