partially commited set_lsn command
Merge branch 'master' into transferring-snapshot-to-replica
added master/replica handshake + transferring snapshot
minor bugs fixed
minor bugs fixed
new attempt for master/replica connect
simple fix
minor fixes master-replica
added old (1.5) version of replica.cc
tests fixed
tests added
tests fixed
test fixes (2)1
replica test result updated
fixes according to CR
minor test fixes
Merge branch 'master' into transferring-snapshot-to-replica

Conflicts:
	CMakeLists.txt
https://blueprints.launchpad.net/tarantool/+spec/start-replication-last-dump

Review fixes:

- New configuration variable 'replication_protocol'
is defined in the configuration file. The original patch
would hand-craft it into generated files.
- Simplified  numeric version id generation.
- Removed timeouts from new sio_* calls. They did't quite work,
especially with blocking sockits. Timeouts should at least use
select(), which updates wait time on exit..
- Removed include cfg/tarantool_box_cfg.h into recovery.cc, instead
passed around all arguments explicitly.
- Removed unused headers.
- reused handshake code in master and replica
- simplified handshake in replica fiber
- removed clutter
- touched here and there.
Merge branch 'transferring-snapshot-to-replica'