Is your feature request related to a problem? Please describe.
Yes, I use a tool like nvm to manage my Node versions. In nvm we have a command nvm ls-remote which lists the Node versions that are available for install so that I can know what to install with the goenv install command and specifying the right version.

Describe the solution you'd like
A command like goenv ls-remote which will return the Go versions available for download and also marks which of the available Go versions have been installed locally by using a different coloring or another way to mark them as already installed, similar to what nvm ls-remote. It will also be good to mark the LTS versions of Go that are available for installation.