Open/pending issues as of Jan 17

[Rich Felker <dalias@libc.org>]

With a quick review of the mailing list since late November I found
the following possibly-open issues:

- resolver search domain support
- preinit_array
- mlock2 syscall wrapper
- mips siginfo_t fix
- avl tree: any changes still pending??
- adding pot file for translators
- unsetenv pointer eval after free
- printf big widths/precisions
- atomic.h overhaul
- dirent.h macros
- dlopen deadlock
- setvbuf

Also, not code issues, but the following possibly-open documentation
issues were found:

- documenting atomic.h primitives contracts
- documenting "known UB" in musl

There were a few other patches that were mostly trivial which I just
committed outright, and the big one, out-of-tree builds, that I
finally committed after some more testing.

Is there anything else I missed that's an open issue right now? Or
requests for prioritizing the above list? I'm going to try to take the
above (and anything else that comes up) and turn it into a plan for
what can reasonably go into the next release.

Rich