Add support for multiple Redis Sentinel hosts

[florianJacques]

This Pull Request adds a new configuration key sentinel_hosts to define multiple Redis Sentinel instances.
No breaking changes are introduced: the existing configuration remains fully compatible.

New Configuration

If only a single instance is used, you can still use the sentinel_host and sentinel_port keys.

For multiple instances, the sentinel_hosts key now accepts a list of Sentinel hosts, each defined by a host and a port:

'sentinel_hosts' => [
    [
        'host' => '127.0.0.1',
        'port' => 26379,
    ],
    [
        'host' => '127.0.0.1',
        'port' => 26380,
    ],
],

[Namoshek]

Looks good so far. Can you please add documentation to the README as well?

[florianJacques]

Looks good so far. Can you please add documentation to the README as well?

Of course! Is Done.

I’ll let you take care of updating the documentation so that it is consistent with your writing style.

[Namoshek]

Thanks, released as v1.2.0.

[florianJacques]

Thanks, released as v1.2.0.

Oops, I think I forgot a comma in the code section of the documentation.