Removed the ColumnStore specific code introduced in this commit:
a7361f0637323b3b1046d0e44c924a4823f09d3a
We attempted to use the ColumnStore engine, but it didn't seem
to perform faster overall. Although running simple projection
queries on the ColumnStore tables seemed a lot faster compared to
MEMORY tables!
Made backup copies of the files in the obsolete directory so we
can view this code more easily if we want to explore ColumnStore
engine tables again in the future.