Clean up GetTor text now that we have a user manual
When the user manual is done (legacy/trac#4069 (closed)), clean up the GetTor text, make it shorter and only include information that is not present in the user manual.
GitLab is used only for code review, issue tracking and project management. Canonical locations for source code are still https://gitweb.torproject.org/ https://git.torproject.org/ and git-rw.torproject.org.
When the user manual is done (legacy/trac#4069 (closed)), clean up the GetTor text, make it shorter and only include information that is not present in the user manual.