Add Format as Table option

[hulien22]

We currently only format results as timeseries, however tables have a different format that can allow for more information.
Some other datasources, such as Prometheus, have an option Format as. This allows for better use of the table and world map panels.

The table should show timestamp, data, as well as metadata. There should also be a way to order and filter out columns (some of this can be done via the panel's settings)

[hulien22]

After a bit of thinking, it seems that this is fairly useless for normal timeseries as their metadata does not change. This is only really useful for the worldmap panel if someone wants to add a geohash as a metadata value, but there is also the option of using a JSON endpoint to choose exact positions that works currently.

There has been a request to be able to view all metadata properties in a table, but that requires a bit more thought on the ui/ux side.

One thing to note is that Format as Table will be useful for multi-valued timeseries.

Closing for now, as there is not much work that can be done on this at the moment.