Powerlevel9k: Improve Go segments

[mingrammer]

The gvm is Golang version management package like virtualenv of python.

How about support gvm for Go like rvm for ruby, nvm for javascript and virtualenv for python?

[dritter]

@mingrammer That would be a great improvement! 👍

Feel free to submit a pull request and do not hesitate to ask if you need help ;)

[bhilburn]

I would still love to see this happen, if there are any Go programmers that are up to the task! =)

[zikes]

I think the Go segment is fairly robust now, anything else on your Go wishlist?

[bhilburn]

Agreed! Thanks for your contributions, @zikes =)