[benchmarks] add nc_one_connection test (not works correct)

Because of how pipe and nc communicates, here is nc strace output:
{code}
...
select(4, [0 3], NULL, NULL, NULL)      = 1 (in [0])
read(0, "HSET 1_key 1_value\n", 8192)   = 19
write(3, "HSET 1_key 1_value\n", 19)    = 19
select(4, [0 3], NULL, NULL, NULL)      = 1 (in [0])
read(0, "", 8192)                       = 0          # Must read from 3
                                                     # instead of STDIN
close(0)                                = 0
...
{/code}
[repo] ignore logs
[benchmarks] rewrite nc part of one_connection to gawk.
[benchmarks] fully rewrite one_connection.sh to gawk.

Not it works correct, and we can already test server with it.
[test] one_connection: improve log messages
[benchmarks] one_connection: use file with random name in "/tmp"

- Delete it after exit (or interrupt)
- Decrease LIMIT to 1000000, because on some systems "/tmp" is tmpfs
[benchmarks] one_connection: add estimate time for run_test_client() function
[benchmarks] one_connection: add number of queries per second
[test] run one_connection.sh after build in travis-ci