sql.py: DbConn.col_info(): Parse array types as sql_gen.ArrayType

sql_gen.py: EnsureNotNull: Support ArrayType types

strings.py: remove_prefix(), remove_suffix(): Added require param to raise aan exception if the string does not have the given prefix/suffix

sql.py: DbConn.col_info(): Moved parsing of user-defined datatypes to Python code, so that parsing for other composite types which also requires both data_type and udt_name can easily be added

sql_gen.py: Added ArrayType

schemas/vegbien.sql: Scope taxonpath instead of taxon with taxonscope, because a morphospecies name is specific to a datasource entity, so it should go in the datasource-specific taxonpath table instead of the datasource-general taxon table

schemas/vegbien.sql: taxonpath: Added otherranks array column to store ranked names without a named column. Documented that ranks with no named column should be stored in this new field instead of in a chain of taxons pointed to by taxon_id. This ensures that only the tree of life uses the taxon table.

schemas/vegbien.sql: Removed no longer used table stemtag, which has been replaced by stemobservation.tag, stemobservation.tags

inputs/ARIZ/Specimen/test.xml.ref: Updated after reinstalling staging table with new sql_io.null_strs

inputs/VegBank/: Added stemlocation/