Make NONE alter not special
Remove misleading tests and fix assumptions
Move tableVersionMap to Persistit only
Move Store SESSION_TABLES_KEY down to Persistit only
Make MTs handle differeing Store behavior
merge nathanlws: Move table version checking for DML from base to Persistit implementations

Merge pull request #1309 from nathanlws/sql-layer/table-version-map-persistit-only
https://github.com/FoundationDB/sql-layer/pull/1309