admin: Remove stale intake documents (#4815)

We had a couple documents that were temporary checklists and status
reports from back when the project was first coming into the ASWF,
reminding us of tasks that needed to be performed.

That was years ago! All done, and OIIO is even a fully
"adopted/graduated" project. Remove the files, which are misleadingly
out of date and no longer needed.

Signed-off-by: Larry Gritz <lg@larrygritz.com>

Author: lgritz