Development workflow and 1.0.0 release

Description

Create a development and release workflowincluding sending a message to the tor-announce mailing list.

Existing workflows that can be used as a base:

• Development - Onionprobe.
• Development workflow - Onionspray.

Tasks

• Create a ChangeLog.md file.
• Create (and document) a development workflow.
• Do the 1.0.0 release (GitLab release will be automatically created once a new tag is pushed).