Add support for clickhouse keeper

[frankwg]

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Signed-off-by: Frank Wong [email protected]

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[odinsy]

Guys, any news about clickhouse-keeper support feature?
ClickHouse recommend using clickhouse-keeper instead of zookeeper, and looks like it's a good idea to have a way to configure it on operator level, what do u think?

[alex-zaitsev]

@frankwg , @odinsy -- we start working on Keeper integration in scope of operator 0.23 release.