OPENNLP-1422 Enhance JavaDoc in opennlp.tools.formats sub-packages

[mawiesne]

Change

• introduces opennlp.tools.commons.Internal annotation to transparently mark classes as 'internal use only' in JavaDoc
• adds missing JavaDoc
• improves existing documentation for clarity
• addresses outdated/lost URLs that were gone with a 404 with appropriate alternatives
• removes superfluous text
• adds 'final' modifier where useful and applicable
• adds 'Override' annotation where useful and applicable
• adds package-info.java files for several sub-packages
• simplifies several constructors, removing duplicate code
• fixes some typos

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[rzo1]

Maybe we should add something similar for @ThreadSafe. Might be a good thing for doc generation in the future.

[mawiesne]

Maybe we should add something similar for @ThreadSafe. Might be a good thing for doc generation in the future.

@rzo1 If you'd open a Jira issue for your idea, I can contribute sth for that.

[rzo1]

Maybe we should add something similar for @ThreadSafe. Might be a good thing for doc generation in the future.

@rzo1 If you'd open a Jira issue for your idea, I can contribute sth for that.

OPENNLP-1424