_Noreturn kw must appear before the function name as per C11 grammar and
clang7 is the first one to enforce that.

Ecb_noreturn macro is defined using _Noreturn keyword if C11 support is
detected; otherwise __noreturn__ gcc attribute is used. The later must
appear after the function parameters list.  These two methods to
annotate a function are inherently incompatible in terms of the token
location relative to the function declaration.

Use gcc attribute exclusively since it is always available.

Support multi-part keys. Allow key duplicate
compaction. Reduce storage cost, encode metadata,
do not store msgpack (except value part).
Reconstruct tuple on read using index schema.

[replication]

JOIN support temporary put to not working
condition: there is no way to access possibly
deleted space schema during the operation
for a tuple reconstruction
(multi-thread).

recreate space key_def during join; enable join

sophia: make every operation asynchronous

sophia: fix join cursor and tests

sophia: implement delayed update operation

sophia: make delete write-only

implement Handler::executeReplace

sophia: merge fixes

make upsert operation an engine specific

sophia: make update logic common to memtx

sophia-integration: switch to Sophia v1.2.3; implement upsert

sophia: add half_commit mode support

This mode disables conflict resolution for
'prepared' transactions and solves the issue with
concurrent write-write conflicts during wal write/yield.

sophia: do not allocate tuple during replace or update; refactoring

sophia: extend and reorganize test suite

sophia: implement box.sophia()

sophia: #681: support or produce error on space::alter

sophia: extend recover tests

sophia: add separate iterator tests

box: enable per-engine select

    * add executeSelect() into engine handler API
    * add MemtxIndex; move preallocated m_position from Index to MemtxIndex
    * remove it->close()
    * remove IteratorGuard class

    note: Sysview and Sophia engines yet share the same select code in
    engine::executeSelect() (which does iterator alloc-free)

box: remove close call from box_iterator_free()

- fix net.box to satisfy strict.lua requirements
- after review fixes
- fix buffer:checksize() in buffer.lua

Implement 'strict' module, which prohibits use of undeclared global
variables.

require('strict').on() turns strict mode on
require('strict').off turns strict mode off

Turn strict on by default in debug build, off in release builds.

ev_stat already uses inotify. Patch libev to add support for
nanosecond timestams in struct stat.

Don't register second-level modules (e.g. box.info) in package.loaded

This patch adds `src/module.h` header file with definition of all public
API functions suitable to use in Lua/C modules for Tarantool. This header
is automatically generated from src/*.h by CMake (`make generate_module_api`)
by extracting code blocks between /** \cond public */ /* \endcond public */
Doxygen-style comments.

Definitions of functions in module.h are frozen and must not be changed by
future commits/releases. A new test case `app/module_api` is added to check
compilation, linkage and loading of Lua modules and functionality of
provided API functions.

Other changes:

 * Convert mysql and pg to use module.h and prepare to convert to .c
 * Fix includes in say.h, coeio.h
 * Rename luaL_pushnumber64 to luaL_pushuint64 and
          luaL_pushinumber64 to luaL_pushint64
 * Add LUA_API macros to public luaL_* functions (actually adds extern "C")

* Fix gh-698: duplicate-key error followed by segfault

* Add long_run test suite, which include test case from the
ticket for memtx and sophia engines.
Result files must be zero-diff

Test script also has been fixed in a number of ways:
  a) crud operation on sophia space always return nil
  b) sophia_space:len() is not monotonous
  c) update of primary key is not allowed

* Fix return of vclock_sum() as wal_writer() result, reuse
it for txn->signature

* Fixed incorrect tuple guard usage in execute_delete()

* Fixed sophia delete operation: return old_tuple as an
exception for SophiaIndex::replace(). Do not skip
wal_write() and correctly set txn->signature

* Put engine commit code after wal_write(), reuse proper
txn->signature. Engine->commit yet can throw an exception
on concurrent transaction conflict or error

* rollback sophia transaction on conflict

* add second test for gh-698; rename and disable zlong_run tests

* make rollback statement engine specific

* make txn_finish() engine specific; use it both by commit/rollback to gc

* refactor execute_delete()

* upgrade sophia submodule: efficient msgpack storage

* engine api: style fixes

Fix a crash due to memory corruption in fio.dirname().
A test case would test nothing since the corrupted Lua heap
doesn't crash on you immediately..

fio.dirname() is tested in fio.test.lua

make sophia snapshot creation right before
environment run.

more snapshot tests.

Build Sophia before trying to link with it.