Launch bash from gitfiend

[HatiGamedev]

Thought it was kind of related to #3 but it is the other way around. Some tasks are taking longer than expected in GitFiend if you are commonly using git bash. But I like the interface for a broader overview and regular tasks.

It would be a nice addition to add a "Launch Git Bash" menu entry, so the repository is opened in bash.

[GitFiend]

Thanks HatiEth. I think this is worth adding.