sql_io.py: put_table(): MissingCastException: Use strings.repr_no_u() instead of strings.urepr() in order to remove the u in u'...' for Unicode strings

README.TXT: After a new import: Updated commands for new subdirs layout

Regenerated vegbien.ERD exports

mappings: Added autogen Veg+-VegCore.to_self.csv, which is Veg+-VegCore.csv joined to itself, and use it as an intermediate map to join to VegCore-VegBIEN.csv. This provides support for two-level chains of mappings in Veg+-VegCore.csv.

mappings/Veg+-VegCore.csv: Changed output root to Veg+, to allow mappings/Veg+-VegCore.csv to be joined with itself idempotently, for supporting multi-level chains of mappings

mappings/Veg+-VegCore.csv: Add pass through /_alt mapping for all terms in this map that are merged with _alt, to allow datasource to define custom mappings that don't pass through the default mapping. This also allows mappings/Veg+-VegCore.csv to be joined with itself idempotently, to support multi-level chains of mappings.

mappings/Veg+-VegCore.csv: authorPlantCode: Added _alt suffix to create the correct priority

union: Exclude empty rows from the output, so that empty mappings from map_0 aren't included when map_1 contains a non-empty mapping for the same term. Note that this causes "No non-empty join mapping" warnings to turn into "No join mapping".

ci_map: Run join_union_sort in quiet mode so that it doesn't add lots of "No non-empty join mapping" warnings to the Comments column

mappings/Veg+-VegCore.csv: scientificNameAuthor: Added scientificNameAuthorship mapping with /_alt/1, to ensure that it has priority over scientificNameAuthor and to ensure that it has an _alt suffix when a datasource contains both scientificNameAuthor and scientificNameAuthorship (such as SpeciesLink)