Bookmark repos and pin tabs

[K3UL]

Problem description I work with a lot of different repositories, but there are a few that I used several times a day.
I keep all tabs open and I usually have to scroll a lot through the tabs.

Preferred solution

The way I see it this could be solved in a nice way with the introduction of two things :

• The ability to mark a repo as favorite and show the favorites in another section on the welcome page, like the recent repos
• The ability to pin tabs

As a bonus, combining these two things, there could be an option "Always pin tabs of favorite repos" so that if I open a favorite it gets pinned.

As another bonus the mechanics (bookmarks and pinning) could be adapted for branches and commits, which is covered in #983 and #1140

Alternatives

I think grouping tabs decreases the pain of tabs scrolling (but it a more clunky way to do what I want, which is quick access certain repos), so this could be related to #991

Screenshots

N/A