Clean up the `src version` output

Created by: stimut

The output of src version uses inconsistent capitalization of "version", and the recommended version can sometimes be a downgrade compared to what is actually installed. The changes in this PR are to:

• standardize on lower-case v in "version"
• add or later to output of recommended version

Fixes sourcegraph/sourcegraph#16850

Created by: mrnugget

Review: Approved

Thank you, @stimut!

Created by: eseliger

Review: Approved

Thanks!

Merged by: mrnugget at 2021-05-21 13:03:15 UTC