* Logs: Optional logs label column

- reintroduces label column that was removed when log details were
introduced
- added to explore and also as a new option to logs panel
- explore column settings now stored in localstorage
- labels are rendered with font size xs
- labels that start with `_` or are called `level` or `filename` are not
displayed
- removed click handlers and moved remaining `LogLabel` logic into `LogLabels`

* Added prop to satisfy interface

* Review feedback

* removed comment

* Changed label of label column switch