- [feature] The behavior of column targeting

- [feature] The behavior of column targeting
in result sets is now case sensitive by
default.   SQLAlchemy for many years would
run a case-insensitive conversion on these values,
probably to alleviate early case sensitivity
issues with dialects like Oracle and
Firebird.   These issues have been more cleanly
solved in more modern versions so the performance
hit of calling lower() on identifiers is removed.
The case insensitive comparisons can be re-enabled
by setting "case_insensitive=False" on
create_engine().  [ticket:2423]