+ Rewrite msgpackffi to use ibuf to use ibuf for temporary allocations
 + Rewrite socket:sysread() to use ibuf for temporary allocations
 + Rewrite socket:read() and socket:write() to use ibuf
 + Add socket:sysread(char *, size) and socket:syswrite(const char *, size)

Replace socket('AF_UNIX', 'SOCK_STREAM', 'ip') with
        socket('AF_UNIX', 'SOCK_STREAM', 0).

Fixes distributions with missing "ip 0 IP" line in /etc/protocols
(e.g. Arch Linux).

Test case

*)added proper cleanup
*)minor fixes and checks

Introduce mpstream API to lua-msgpack encoder, which allows it
to encode msgpack into any memory source. The streaming API
should make it possible to encode even directly to network.

Patch region allocator to support the new API.
Patch iobuf/obuf output buffer of iproto to support the new API.

Extract Exception::clear(), Exception::move(), fiber()->exception
into struct diag methods. This refactoring makes desired logic
to be more clear.

finalizers.test marked as long run in suite

 *) added stress test for snapshotting
 *) moved finalizers.test.py to long_run

set test-run module in gh-3 branch for review

closes gh-856

Backport fix from tarantool/mysql by Anton Reznikov

Implement box.once().

Right now there is a race in box.once(), this is somethign we'll
need to fix when we have master election on simultaneous bootstrap.

The patch merely "establishes" the syntax which is going to work
most of the time.

Don't log exceptions of dead joinable fibers - it will
be logged by the caller, so avoid double logging.

recover_remaining_wals() is now more like an iterator,
vclockset_match() is only called when there is no current WAL.

Add a test case for gaps in LSNs.

- add forgotten latch.h, fix latch.h header guards
- make sure the stuff in thread is thread-safe and exception-safe
- remove snapshot_pid and update the docs.
- remove empty lines/trailing spaces
- move xlog_open()/xlog_close() to the snapshot thread
- use cord_costart() to have fiber infrastructure
 in the checkpoint thread, rather than run checkpoint
 in sched fiber
- remove #include <fiber.h> from memtx_engine.h, it's not
  needed there
- remove errNo() method from base class Exception, anything
  with an error no inherits from SystemError. Moreover,
  now that we have a rich exception infrastructure at our
  disposal, we should switch to using it in engine API,
  so in future returning error no will be replaced
  with exceptions.

Add a directory watcher, in addition to the file watcher.

Chagne wal_dir_rescan_delay default value to 2, since now it's
merely a backup.

Fix a crash in rollbackStatement() when rolling back a
statement trying to access a non-exissting space.

space_cache_find() is called before txn_begin_stmt(), thus
there is no statement object, nothing to roll back.

Remove iditioc tests from the suite.

Change the logic of recovery_finalize() to open
the next xlog if the last xlog had zero rows.
Add a test case.

Remove recovery->finalize, use recovery->writer instead.

Hard-code 1-based error message for now, we'll use field names
in the future anyway.

Remove trailing spaces, fix typos.

Old sql code completly reomoved from tests
box/sql.test, big.sql.test refactoring
sql.tests enabled in big and box suites
Replication tests sql refactoring
parallel call.test sql refactoring
box.error test fixed in call.test

After review fixes:
1. rename remote to iproto
2. remove old sql tests
3. update test-run

*) Splitted rlist initializer to RLIST_HEAD_INITIALIZER(..) and RTREE_LINK_INITIALIZER