It differs from the rest of the rephist code in that it's actually
necessary for Tor to operate, so it should probably go somewhere
else.  I'm not sure where yet, so I'll leave it in the same
directory, but give it its own file.

Make them only include the headers that they needed, and sort their
headers while we're at it.

Since this is completely core functionality, I'm putting it in
core/mainloop, even though it depends on feature/hibernate. We'll
have to sort that out in the future.

(It turns out that some of the functions in router.h didn't even
exist any more, so I just got to delete their declarations completely.)

Note that I haven't separated the headers yet (there's still an

This is preparation for having a routermode.h as well

This is also used by onion services, so it needs to go in another
module.

Bug 27781; bugfix on 0.3.5.1-alpha.

Because with arm on OpenSSL <1.1 we don't define USE_EVP_AES_CTR, we
need to include crypto_util.h here.

Fixes a stem test failure; bugfix on c7ce6b98. Bug
not in any released Tor.

Missed in 667a6e8f.

Parts of this C file naturally belong in dircache, dirclient, and
dircommon: so, move them there.

Signed-off-by: David Goulet <dgoulet@torproject.org>