sql.py: DbConn: Added std_code()

db_xml.py: Removed into_table_name() because this functionality is now handled by sql.into_table_name()

sql.py: into_table_name(): Also parse hierarchical tables (mappings with a rank column) using a special syntax

sql.py: put_table(): Fixed bug where distinct_on included columns that were not in the input table, and were thus incorrectly taken from the LEFT JOINed output table

sql.py: track_data_error(): Do nothing if cols are empty, because mk_track_data_error() requires at least one col. mk_track_data_error(): Assert that cols are not empty because VALUES clause requires at least one row.

bin/map: by_col: Pass on_error to db_xml.put_table() that calls ex_tracker.track()

sql.py: put_table(): No handler for exception: Pass exception to on_error() instead of raising a warning, so that error message can be formatted

db_xml.py: put_table(): Pass on_error to sql.put_table()

db_xml.py: put_table(): Take on_error param like row-based put()

sql.py: put_table(): Take on_error param