Write git status(es) into .livesync_mutex about livesync HOT 4 CLOSED

I updated the git summary accordingly: 6f9757c.
Now the mutex file looks like this:

Falkos-MBP 2022-09-02T07:59:38.620688

/Users/falko/Projects/livesync --> ~/livesync
[f3dddb0]
## main...origin/main
 M livesync/livesync.py

from livesync.

Implemented in b8f6299 and f3dddb0.

The git information needs to be passed into the mutex set and is_free methods, but it works. To avoid issues with quotes when echoing the multiline string into the mutex file, they are replaced with single quotes.

from livesync.

Random thoughts:

• Now livesync depends on git being installed. We might want to make this optional.
• git status does not show the commit hash. Maybe there's a better representation of the current status.

from livesync.

We could simply add the shortend hash above the git status call: https://stackoverflow.com/a/7617078/364388

from livesync.