- Added CI step to publish on release tags.
- Fixed npm complaining about permissions in CI.
- Fixed CI audit failing on dev dependencies.
- Switched to using 'npm ci'.

feat: Changed starting serial number to be an optional parameter; random serials will assigned if it is ommitted.

BREAKING CHANGE: Certificates and private keys are now handled as buffers rather
than strings.

BREAKING CHANGE: By default, temporary files are no longer scrubbed
before deletion; all functions/methods that generate temporary files
now accept a boolean option to enable scrubbing.