Unused variable are validated across files in pack

Closes #438
Rename a failing test case to be more explicit.
Rename a failing test case to be more explicit about what is being tested there.

Also added a resolving test case to showcase the root cause.

Refs #865
Update README 0.9.16.md

Duplicated 'we'.
Merge pull request #1031 from gaku/patch-1

Update README 0.9.16.md
cleanups
Fixed test folder name