Support Nullmarked on module-info (JPMS)

[xenoterracide]

If a module-info exists and it has the Nullmarked annotation, all packages contained within should be treated as though they are also Nullmarked unless they are NullUnmarked, and etc... you get it. I know this behavior is desired, so this is mostly just so it can be tracked.

[msridhar]

We should and will eventually support this. But generally speaking, at this point it doesn't seem like a library can rely just on annotating module-info to get the desired behavior; see jspecify/jspecify#496 (comment)

[xenoterracide]

JPMS, getting in its own way for a decade, and not being helped along by the community :/