Option for topological ordered log tab

**Is your feature request related to a problem? Please describe.**
I prefer topological ordering of commits (as seen in `git log --topo-order`) to chronological ordering in commit logs, as I find it easier to understand the history (without looking at a commit graph) due to the way it groups commits from one branch together

**Describe the solution you'd like**
This could either be implemented as a keybinding which toggles commit ordering between chronological and topological, or as an entry in a configuration file. (or both).
Though since gitui doesn't have a general config file (that I'm aware of? just the keybindings and theme ones?), the latter might not be the right solution

**Describe alternatives you've considered**
The git CLI itself has an option for logs to be ordered like this using the `--topo-order` flag, which can be formatted using the ``--pretty`` flag
E.g.
```
git log --topo-order --date=short --pretty="%Cred%h%Creset %<(20,trunc)%an %Cgreen(%ad)%Creset %s"
```
It works, and I have an alias for this, but it's a little awkward to use because I have to exit gitui to run it, and then enter back into gitui after. And obviously it'd be better if it was interactive as well

**Additional context**
I'd be interested in having a go at implementing this myself, though I'm not super familiar with Rust, so some pointers would be helpful

Das Issue nennt keine Dateien oder Tests; beginne damit, den Einstiegspunkt für gituis Commit-Log und den Code zu finden, der den Git-Log-Befehl erstellt. Überprüfe die bestehenden Pfade für die Konfiguration von Tastenbelegungen und Themes und verifiziere anschließend, dass die gewählte Sortierreihenfolge umgeschaltet oder konfiguriert werden kann und sich im interaktiven Log widerspiegelt.

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