mappings/VegCore-VegBIEN.csv: taxonName->taxonomicname: Use new _has_taxonomic_name() instead of _is_higher_taxon(), because it's more specific to the filtering task for this field

schemas/vegbien.sql: Added _has_taxonomic_name() for lower taxon ranks that typically have a globally unique taxonomic name

schemas/functions.sql: Removed unit conversion functions that take a text input, since casts to the parameter type (double precision) are now automatically performed by sql_io.put_table(), using sql.parse_exception()'s function MissingCastException parsing

mappings/VegCore-VegBIEN.csv: _is_higher_taxon() calls: Default to true if the rank can't be parsed to a taxonrank enum value

sql_io.py: put_table(): is_function: Moved definition of wrapper function inside try block of main loop because the creation of the empty pkeys table (whose row type is needed for the wrapper function) can itself produce MissingCastExceptions, which must be thrown inside the loop in order to be handled properly

db_xml.py: put(): Indicate no parent_ids_loc using no_parent_ids_loc sentinel instead of None to support parent_ids_locs that are equal to None (e.g. if the parent node had an error). Always forward parent_ids_loc to children with fkeys to parent, even on error, because the parent table may not be required for the child tables to be valid, such as for taxonomic-data-only datasets that nevertheless have nodes for the non-taxonomic tables in their mappings.

sql.py: parse_exception(): types cannot be matched MissingCastException: Use the first type as the type to cast to instead of text

sql.py: parse_exception(): InvalidValueException: Fixed bug in regexp where can't use .*? before (?:...)? surrounding matched value, because it prevents the value from being matched now that it is optional

inputs/.NCBI/nodes/header.csv: Updated for new staging table format, which includes a row_num column in each joined table

inputs/.NCBI/nodes/create.sql: Updated for new src table names