Server help option

[yurriy]

I hereby agree to the terms of the CLA available at: https://yandex.ru/legal/cla/?lang=en

Category:

• New Feature

Short description:
Added --help/-h option to server
Output:

~/ClickHouse/build$ ./dbms/programs/clickhouse-server -h
usage:
clickhouse-server [OPTION] [-- [ARG]...]
positional arguments can be used to rewrite config.xml properties, for
example, --http_port=8010

-h, --help                        show help and exit
--daemon                          Run application as a daemon.
--umask=mask                      Set the daemon's umask (octal, e.g. 027).
--pidfile=path                    Write the process ID of the application to
                                  given file.
-C<file>, --config-file=<file>    load configuration from a given file
-L<file>, --log-file=<file>       use given log file
-E<file>, --errorlog-file=<file>  use given log file for errors only
-P<file>, --pid-file=<file>       use given pidfile

[alexey-milovidov]

(obsolete)

Let's write .sh test. See /dbms/tests/queries/*.sh
At least check that the help exists.--