sql.py: DbConn._db(): Setting serializable isolation level: Always set this (if self.serializable is set), even in autocommit mode, because autocommit mode is implemented by manual commits in the DbConn wrapper object rather than using the underlying connection's autocommit mode (which does not allow setting the isolation level)

sql.py: DbConn._db(): Setting search_path: Use `SET search_path` and `SHOW search_path` instead of combining the old and new search_paths in SQL itself using `SELECT set_config('search_path', ...)`

csv2db: ProgressInputStream: Use default progress message 'Read %d line(s)' because there is not necessarily one CSV row per line, due to embedded newlines

input.Makefile: Staging tables: import/install-%: Only output to the log file if log option is non-empty (which it is by default)

csv2db: Support reinstalling just the errors table using new errors_table_only option

sql.py: Added drop_table()

schemas/vegbien.sql: method: Changed indexes to use `COALESCE` to match what sql_gen now does

schemas/vegbien.sql: specimenreplicate: Added indexes using COALESCE to match what sql_gen does

schemas/vegbien.sql: locationevent: Added indexes using COALESCE to match what sql_gen does

schemas/vegbien.ERD.mwb: Synced with schema