v0.0.16

Changelog

• 8115e62 GitHub: improve error message when SSH key resolution fails.
• 09eacae Slackbot: include the commit message, if one is available (e.g. push event), in the notification.
• f1b1d55 Switch us over to the Slackbot, so messages can be updated in-place.
• bcac85e action: setup-go
• 409c074 actions: build and vet on nscloud runners
• 09b3be5 build(deps): bump github.com/cloudflare/circl from 1.1.0 to 1.3.3 (#8)
• 3814c42 readme: typo
• f10c7ba workflows: change confusing name to workflow