Consider implementing "of" rule as equivalent of ES should + minimum_should_match

[jclaveau]

• https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-minimum-should-match.html

• Example:

[ 3, 'of',
    ['field', '=', 'bla'],
    ['field', '=', 'foo'],
    ['field3', '>', 8],
    ['field2', '<', -5],
]

or maybe

[ '3 of',
    ['field', '=', 'bla'],
    'or',
    ['field', '=', 'foo'],
    'or',
    ['field3', '>', 8],
    'or',
    ['field2', '<', -5],
]