Fix stat_add_date for members in stores
Closes #361 (closed)
What does this MR do?
- sets the date at which a user was added to a store in two more cases: when a new store is created and when a user is added without a request
- removes the fallback from StatsControl which sets the date to the creation date of the store or the first fetch
How confident are you it won't break things if deployed?
Very confident, since these are only small fixes and all tests pass.
Links to related issues
- added a test, or explain why one is not needed/possible: seems unnecessary
- no unrelated changes
- asked someone for a code review
- joined #foodsharing-beta channel at https://slackin.yunity.org
- added an entry to CHANGELOG.md (description, merge request link, username(s))