Adjust the getenv API

The getenv call in sys/config was renamed to getenvs and now uses
the splat operator so that arrays don't have to be passed in. A
new function called getenv was added which takes a single argument
and returns a single value back (for ease of use).
Fix disclosure date and newline as pointed by @wvu-r7
Land #2821, @OJ's mod for the getenv API
Land #2804 for real (thanks, @jvazquez-r7!)

It was the wrong time to mess with my workflow.