Merge branch 'master' of https://github.com/tarantool/tarantool

doc/sphinx/reference/socket.rst

src/box/iproto.cc

src/box/lua/call.cc

src/box/recovery.cc

src/coio.h

src/evio.h

src/lua/bsdsocket.cc

src/lua/fiber.cc

test/app/snapshot.test.lua

test/box/bsdsocket.result

test/box/bsdsocket.test.lua

test/box/call.result

test/box/call.test.py

test/wal_off/snapshot_stress.result

test/wal_off/snapshot_stress.test.lua