Add git blame plugin

[rdbende]

Resolves #1289

[Akuli]

Maybe the blame functionality should be behind a right-click, so that it doesn't consume CPU power and e.g. make your laptop battery run out quicker.

[Moosems]

Most other editors wait for a hover on a line to render or the first line selected/the insert location.

[rdbende]

Currently this doesn't do anything, simply prints the info, but yeah, I was wondering when it should actually show it, and where.

[Moosems]

I would use the selection/insert and hover (if hover is possible with tkinter Text (maybe a tag_add but that adds more processing time).

[Akuli]

and where.

Found this screenshot of vscode online, IMO it's a pretty good option:

It assumes that the editor is wide enough to fit stuff to the side, but git blame needs a wide window in general, even on the terminal.

Maybe the best way to show the stuff would be to not actually insert something to the text widget, but add a label with the same font and background color as the text widget.

[Akuli]

Or maybe show the commits on the left side, similar to github (press b when looking at a file):

IMO it would be enough if copying the commit hashes to clipboard was easy, so that you can take the commit hash to terminal for git show or git checkout or git revert, for example.

[rdbende]

Inserting it to the text widget screws up the highlighting, so then I'll go with the label.

[rdbende]

And what about putting it in the status bar, next to the line and column numbers?

Line 12, column 34; changed by rdbende five months ago • this is a descriptive commit message

Then we don't have to worry about scrolling, and more text would fit on the screen. Although this way it would be kinda weird to have a timeout before the label appears.

[Moosems]

In VS Code when you click on a git blame it will show the change on the line in a small popup, that would be cool to have.