objc/Object.h is gone in clang 3.2.

Use an own root class for all Tarantool objects.

Fix compile on older gccs.

(https://bugs.launchpad.net/tarantool/+bug/1169200)

No test case since the bug only manifsets itself under
concurrent load.

With addition of on_disconnect triggers, iproto_session_destroy()
was invoked from two places: the request handler code and
iproto_session_disconnect callback.

This could destroy the same session twice. Worse yet, it would
be put to the session cache twice, as a free session, and then
used twice for two different client sockets.

This could end up in an unpredictable mess, best case: libev
event loop runs infinitely since libev fd has events, while
session->input.fd is already set to -1 any attempt to use the
session ends up with an exception. At the same time the session
in this condition can not be destroyed since it's impossible to
tell libev forget about a file descriptor about which we already
know nothing.

A fix and a test case for Bug#1075677
"incorrect conversion from boolean lua value to tarantool tuple".

Support boolean in conversion.

Replication relay was created (forked) after initialization
of slab allocator, and, consequently, had a very large address
space. The memory wasn't used really.

Initialize slab allocator after creation of a replication
relay process.

No test case since we don't have automation to detect that sort
of problems.

Review comments.

Conflicts:
	include/fiber.h

Remove added logging, a message with 'saving snapshot %filename'
is already printed to the log by the child. It contains
snapshot pid. Snapshot fid is not as useful once the bug
is fixed.

https://bugs.launchpad.net/tarantool/+bug/1162797

by SIGUSR1 tarantool
- didn't touch box.info.snapshot_pid
- didn't waitpid for snapshot process

Conflicts:

	include/fiber.h