Failing test
Remove unique/null specialization, now stored as regular indexes.

Fixes #539
Fixes #603
Fixes #675
Bump data version
Do a little less in IndexRowBuffer
Test for concurrent unique index
merge nathanlws: Simplify UNIQUE index representation

Merge pull request #1214 from nathanlws/sql-layer/simplify-unique-indexes
https://github.com/FoundationDB/sql-layer/pull/1214