Add a test that demonstrates the subquery join manifestation.
Add a test with the other manifestation.
Put subquery source with limit into more standard form.
Now get reasonable plans.
merge MMcM: Problems associated with semi-joins via IN with a subquery that has a LIMIT

Merge pull request #1152 from MMcM/sql-layer/semi-join-subquery-limit
https://github.com/FoundationDB/sql-layer/pull/1152