cmd/tests: Add README doc file

[Octavian Voicu]

2011/8/31 Alexandre Julliard <julliard at winehq.org>:
> That sort of thing should be on the wiki. READMEs in the source are
> never maintained properly.

Speaking of obsolete documentation, we should remove the
documentation/ChangeLog.* files. They haven't been updated since wine
1.0 and are confusing. I tried sending a patch to remove them, but the
patch had 9 MB and I'm guessing it didn't go through. Only you can
remove them I guess, if you agree :)

Octavian