Tests for row value constructor optimization. Query more test for salted table using RVC construct. Optimizer tests for tables with secondary indexes and using RVC construct
Merge pull request #472 from samarthjain/master

Tests for row value constructor optimization. Query more test for salted...
Bug fix for altering salted table
Fixes for altering a salted table
Remove unused variable
Disable OR optimizations for mix of RVC and non RVC