[Checkers] Questions about annotations repository

[Matt Papi]

> 5. annotations/notes-compiler.txt seems to be out of date.

It is, as are a few other readme/notes files. Updating these files is
something I intend to work on early next week.

> 6. What is the "annotations/disassembler/" directory?

Yes, it's the pre-langtools version of javap. I don't think there's
anything of value there anymore, but I'll check it first before
deleting it.

- Matt