[feature] dockerized version

[stefanoj3]

Hello, would you accept a PR to dockerize this application?
I personally like the possibility to run software in containers so I don't have to worry about installing them on my system.

[stefanoj3]

If you are not familiar with docker and wanna have a look at what I mean, check: https://github.com/stefanoj3/dirstalk#-download

You can easily run dirstalk using

docker run stefanoj3/dirstalk dirstalk <cmd>

this will never install the application on your system, and you will be able to run it inside of a sandbox (the container).