[patch][gold] Add a tool for dumping incremental linking information

[Ian Lance Taylor]

Rafael Espindola <espindola@google.com> writes:

> An updated patch is attached. One thing I was not sure was if I should
> keep the "internal" namespace when moving the structs to the header
> file. I kept it. Let me know if you think I should remove it.

Please remove it.  Put them in the gold namespace.

OK with that change.

Thanks.

Ian