SERVER-39698 Make $regexFind, $regexFindAll, and $regexMatch error if the regex is invalid

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• Closed

SERVER-39694 Implement $regexMatch as syntactic sugar on top of $regexFind

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• Closed

SERVER-37848 Test $regexFind with regex that meets and exceeds the capture limit

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• Closed

SERVER-39696 Implement $regexFindAll

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• Closed

SERVER-11947 Add a regex expression to the aggregation language

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• Closed