Use edit_settings to open settings

[rchl]

Also, add commands for opening preferences and key binding preferences
to command palette and clean up some trailing spaces.

[rchl]

@nikoargo would you be willing to let someone take over the maintenance of this package? I'd be willing to do a couple of needed changes.

[FichteFoll]

@nikoargo, as per my announcement earlier this year regarding handing out maintainership rights for abandoned repos, I have added @rchl as a maintainer for this repo by his request. I am confident there won't be any problems with this. If there are, don't hesitate to approach me.

@rchl, please also ensure to not break older installations of the package by adding a version constraint and switching to tag-based releases, since this package is still using branches.

[adzenith]

@FichteFoll That seems reasonable. My apologies for lack of replies here - I have much less time to work on open source projects these days now that I have children.
@rchl Welcome! Let me know if I can help with anything!