Add `--lts` flag for `ls-remote`

[chesskuo]

While I list all remote version, I prefer to show LTS version only.

I thought this is more convenient to list what user's want.

Thank you.

[halshar]

ahh, I thought the ls-remote had --lts flag but found nothing in documentation, so came looking here but it's been 1.5 years and no update for this PR :(

[sdavids]

PR has been merged … so this issue can be closed?

[chesskuo]

oh, thank you for your inform.
i would close this issue now.