bin/map: Logging: Print debug messages (level > 1) prefixed with their level, to distinguish higher- and lower-level debug messages

sql.py: put_table(): Only display warning for exceptions with no handler (which are unexpected), not missing mappings for NOT NULL columns (which are normal in datasources without those columns)

sql.py: put_table(): Log summarizing debug messages with a level of 1.5 so they will be displayed even when the major SQL queries (which have a level of 2) are not shown

bin/map: Provide a log_debug() function to sql.connect() if verbosity > 1 rather than >= 2, to support fractional verbosities

sql.py: log_debug_none: Fixed bug where needed to take kw arg level to work with verbosity-based logging

bin/map: Allow fractional verbosity values

sql.py: Functions that version created tables, functions, etc. if they already exist: Use (default) exc_log_level=4 to hide the unsuccessful attempts to create items that already exist and show only the successful attempt

sql.py: DbConn.run_query(): Added exc_log_level param to specify a different log_level if the query throws an exception. This will useful for functions that version created tables, functions, etc. if they already exist.

sql.py: DbConn.run_query(): Removed no longer accurate doc comment, because that functionality is now in module-level run_query()

sql.py: Specify log_levels for minor queries so they can be excluded from the debug output