Sort the Estimation Matrix from Newest to Oldest

[xeronimus]

Discussed in https://github.com/Zuehlke/poinz/discussions/369

^{Originally posted by **Fraser35** September 6, 2023} As a team, we want to compare previous estimations when sizing something new, but generally more recent estimations will be more relevant than older ones. It would be great to have the default sorting from Newest to Oldest, or even better to be able to select what sorting to be used (a bit like the sorting available on the backlog, but probably with different options)

Acceptance Criteria

• By default, the stories within the columns of the Estimation Matrix are sorted. Newest on top. (creation date descending)
• user can cllick a "Sort Button" on the top right corner of the Estimation Matrix, next to "Include Trashed stories".
• On click, a dropdown appears with 4 sort options Newest Oldest Title A-Z Title Z-A
• The stories within the columns of the Estimation Matrix get sorted accordingly

[xeronimus]

implemented. included in 0.20.1