Temporary commit.
Merge branch 'master' of github.com:tarantool/tarantool into fiber-file-io

Conflicts:
	src/CMakeLists.txt
Fix #420: fiber.cancel() assertion `!(f->flags & (1 << 2))' failed
Fix #429: Replication relay crash with background=true
Fix #424: Merge socket:read() and socket:readline()
fiber-io tests.
Merge branch 'master' of github.com:tarantool/tarantool into fiber-file-io
Cleanup code.
Don't use static variables.
Rename dfio to coeio_file.
Merge remote-tracking branch 'origin/gh-429-replication-crash-background'
Merge remote-tracking branch 'origin/gh-424-socket-readline' into stable
Merge remote-tracking branch 'origin/stable'

Conflicts:
	test/box/fiber.result
	test/box/fiber.test
Merge remote-tracking branch 'origin/stable'

Conflicts:
	test/box/fiber.result
	test/box/fiber.test
Merge branch 'stable'

Conflicts:
	test/box/bsdsocket.result
	test/box/bsdsocket.test
Merge remote-tracking branch 'origin/master'

Conflicts:
	test/box/fiber.result
	test/box/fiber.test.lua
'fio' (cooperative file I/O) package: style fixes

Add comments, renames.
Merge remote-tracking branch 'origin/master' into fiber-file-io
Merge branch 'master' of github.com:tarantool/tarantool
Merge branch 'ocelot-master'