sql_io.py: put_table(): mk_main_select(): Fixed bug where the table of each cond needed to be changed to insert_in_table because mk_main_select() uses the distinct table rather than the full input table

sql_gen.py: with_table(): Support columns that are wrapped in a FunctionCall object

sql_gen.py: index_cols: Store just the name of the index column, and add the table in index_col(), in case the table is ever copied and renamed

Moved error tracking from sql.py to sql_io.py

sql_io.py: put_table(): Use sql.distinct_table() to uniquify input table, instead of DISTINCT ON. This avoids letting PostgreSQL create a sort temp table to store the output of the DISTINCT ON, which is not automatically removed until the end of the connection, causing database bloat that can use up the available disk space.

sql_gen.py: suffixed_table(): Use concat()

sql_gen.py: with_default_table(): Remove no longer used overwrite param

sql.py: distinct_table(): Return new table instead of renaming input table so that columns that use input table will continue to work correctly

sql_gen.py: Moved NamedCol check from with_default_table() to with_table()

sql.py: distinct_table(): Fixed bug where empty distinct_on cols needed to create a table with one sample row, instead of returning the original table, because this indicates that the full set of distinct_on columns are all literal values and should only occur once