Support sets [DATAJDBC-113]

[spring-projects-issues]

Jens Schauder opened DATAJDBC-113 and commented

An entity with a reference to a sets of entities or should persist/load those collections with the referencing entity

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Referenced from: pull request #15

[spring-projects-issues]

Jens Schauder commented

I narrowed the scope of the issue to just Sets, since it was getting already large enough