[ENHANCEMENT] system version

[wilmoore]

As requested in #28.

This is a nice-to-have (i.e. non-critical) since there are alternative ways to proceed; for instance:

1. do not use system version -- it is usually outdated pretty quickly.
2. install/compile a local version that matches the system version so you can switch to it.

That being said, if we can find a clean, maintainable, and low lines of code way to do this; great.

[wilmoore]

After a lot of thought, I have no plans to support this. It is a pretty superfluous feature that doesn't add much value to the project besides extra code.

Personally, I tend to switch once per project (via tmux) so switching a bunch of times is generally not a pattern I see. Even if I did switch multiple times, having the path show up a few times isn't going to hurt anything.