Better save managements

It's easy to accumulate lots of save files now in the game; especiallly when the auto-save function is turned on. And it is inconvenient and inefficient to look through all the saves to find the specific one you want. Thus I feel there could be a vast quality of life improvement regards to save management.

Here are some ideas:

1. Categorized saves:

I noticed that currently game simple put all save files in ".../Documents/Endless Space 2/Save Files" with a folder marked for steam cloud save. It would be much easier to sort saves if different saves form different game sessions are kept in their own folder. And in-game save management menu reflects that structure.

2. Rename and duplicate saves:

Rename saves can definitely be useful for example: to quickly rename an auto-save to remind yourself there is a bug to be reported; or there's something cool just happened, etc.

3. Sorting options:

Sort games with turn finished, races choosen, galaxy size, etc. 

4. Game status preview:

Show the basic info of an save, like turns, planets colonized, FIDS production of the selected save or show the data for latest save when selecting specific session.