* rename 'time' to 'clock'
* remove time.bench64, I can't think of a use case

Regression by 0b17f366

Explicitly close net.box connection on error.

Partially reverts squashed 316d4e3a

This regression introducing during replacing port_ffi with port_buf
by 2fcce449

iproto thread can add quirks to thread scheduling, replace
single-call yields with yields in a loop.

Correct return value of ipc_channel_put(), since
it may return an error if the channel is closed.

Make get/put functions inline.

Remove a public declaration for ipc_channel_is_readonly() (towards
removing the concept of readonly altogether).

after review fix: remove group name param in config.

gh-918 tarantoolctl group support implemented with default user group

This test was disabled by me during 1.6 async-master-master development.
Since Tarantool doesn't use proc_title for replication status anymore,
I added a new test that check box.info.replication.

Prepare for multi-master.