As a product owner, I want to see who have changed the order of the issues

Description

As a product owner, I want to see who have change the order of the issues. Otherwise, somebody re-odered them and nobody know who, when, what, how to reverse.

Acceptance criteria

• when issue 100 is moved so that it stands between 99 and 101, all issues 99, 100 and 101 have "system log"
• In issue 100, "Tech-team-1 re-ordered this issues between #99 and #101"
• In issue 99, "Tech-team-1 re-ordered #100 after this issue"
• In issue 101, "Tech-team-1 re-ordered #100 before this issue"

Links / references

Introduced by gitlab-ce#21264