Add a test that demonstrates the problem.
Adding a Project may get in the way of columns that go from its source(s) to something other than the final output.
Now get expected result.
merge MMcM: Additional columns may need to be added to a Project

Merge pull request #914 from MMcM/akiban-server/sql-map-folder-project-required-columns
https://github.com/FoundationDB/sql-layer/pull/914