count DATA cells with stream ID 0 as delivered for SENDME purposes

Found while investigating 8093, but probably not the cause of it,
since this bug would result in us sending too few SENDMEs, not in us
receiving SENDMEs unexpectedly.

Bugfix on the fix for 7889, which has appeared in 0.2.4.10-alpha, but
not yet in any released 0.2.3.x version.
Check for orconns and use connection_or_close_for_error() when appropriate in connection_handle_write_impl()
Believe that v3 dirauths always serve extra infos.

Clients should always believe that v3 directory authorities serve
extra-info documents, regardless of whether their server descriptor
contains a "caches-extra-info" line or not.

Fixes part of #11683.
Turn --enable-buf-freelists off by default
Add --disable-mempools configure option
Turn --enable-mempools off by default
Add changes file for bug11476
Eliminate #ifdef ENABLE_MEMPOOLS in packed_cell_new/free()
Merge remote-tracking branch 'andrea/bug11476'
sandbox: revamp sandbox_getaddrinfo cacheing

The old cache had problems:
     * It needed to be manually preloaded. (It didn't remember any
       address you didn't tell it to remember)
     * It was AF_INET only.
     * It looked at its cache even if the sandbox wasn't turned on.
     * It couldn't remember errors.
     * It had some memory management problems. (You can't use memcpy
       to copy an addrinfo safely; it has pointers in.)

This patch fixes those issues, and moves to a hash table.

Fixes bug 11970; bugfix on 0.2.5.1-alpha.
Documentation fix: DataDir/status/* -> DataDir/stats/*

Our documentation had the name of this directory wrong.
sandbox: allow access to various stats/*-stats files

Fix for 12064 part 1
changes file for 12064_part1
sandbox: allow access to cookie files, approved-routers

fixes part of 12064
sandbox: refactor string-based option-unchanged tests to use a macro

There was too much code duplication in doing it the old way, and I
nearly made a copy-and-paste error in the last commit.
sandbox: allow reading of hidden service configuration files.

fixes part of 12064
Postpone fetches based on should_delay_dir_fetch(), not DisableNetwork

Without this fix, when running with bridges, we would try fetching
directory info far too early, and have up to a 60 second delay if we
started with bridge descriptors available.

Fixes bug 11965. Fix on 0.2.3.6-alpha, arma thinks.
Merge branch 'bug11965_v2'
sandbox: Correct fix for hs part of 12064

Bugfix on cfd0ee514c279bc6c7b; bug not in any released version of tor
Make sandbox.c compile on arm

This is a minimal set of changes for compilation; I need a more
recent kernel to test this stuff.