The package overview documentation is not part of the output JavaDocs

[toddjonker]

The source tree includes overview content that is supposed to be part of the JavaDoc entry page. This is critical first-contact guidance to direct new users to how to approach the library, and sets important global expectations such as thread safety, non-canonicalization, and so on.

However, this content is not present in the published JavaDocs, so something has gone awry in the build process.

[toddjonker]

Related: #497 : A large number of implementation-detail classes are also being erroneously documented, which I reported 13 months ago.