Update dependencies

Deal with several low-priority security issues by updating all dependencies.
Breaking: now requires node v16 or higher.

Add --root to command line

• breaking drop node 12 support, test on node 18
• updated all dependencies and GHA actions
• added --root CLI option to set the root URL for the API (@walkingriver)

Fix typescript types

Fixed #14

v2.0.0

[breaking] Only support node 12+
[chore] Update all old dependencies
[chore] Switch to yargs from `optimiset
[feature] Add API key support (thanks to @icedawn)