Remove Blocks of #if 0

Removes code blocked out using #if 0.

Changes:

 * column_data_dialog.cpp
 * data_access.cpp
 * data_table.cpp
 * resource_selector.cpp
Remove Code For Using Old Schema

Removes code conditionally compiled in using #ifdef USE_OLD_TABLES
on the grounds that it wouldn't make sense to go back to the old
database schema, i.e. prior to adding support for datacenter re-
sources, etc.

Changes:

 * data_access.cpp
 * pt_main_window.cpp
 * resource_selector.cpp
 * selection_dialog.cpp
Remove Metric Hack

Removes code implementing a hack for metrics that is no longer
used (the #define that enabled the code was commented out).

Changes:

 * selection_dialog.cpp
Remove Bhagya Y Comments

Removes comments added by a student to mark their code.

Changes:

 * data_access.cpp: Remove all 'Bhagya Y' comments.
Remove 'smithm' comments

Removes comments added by a student explaining work done during the
Qt 3 to 4 transition.

Changes:

 * data_access.cpp
 * data_access.h
 * data_table.cpp
 * dataset.h
 * file_options_dialog.cpp
 * pt_main_window.cpp
 * resource_type_and_name.h
 * result_table_cursor.cpp
 * result_table_cursor.h
 * selection_dialog.cpp
 * tg_barchart.cpp
 * two_d_table.h
Scrub More Student Names

Scrubs a last couple of comments with student names.

Changes:

 * data_access.cpp