Add matched_queries field to SearchHit.

[mdgilene]

Closes #1514

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[sothawo]

Sorry for the delay, just have been looking at this PR and seen that I have not submitted the review, although I did the review when you submitted the PR. I could have sworn I had hit the submit button.

Two minor places: Spring Data baseline is Java 8, so there are two places that need to be changed.

[mdgilene]

Ahh Java 8 vs 9 didn't even cross my mind. Fixed!

[sothawo]

Thanks again for this PR.