mk_select(): Support join conditions with literal values

sql.py: mk_insert_select(): embeddable: Don't cache function_query because function def could change and then change back

sql.py: with_savepoint(): Renamed savepoints to have "level" prefix, since the # indicates the level #

sql.py: get_cur_query(): Also accept input params to combine with input_query, and pass input params when get_cur_query() is called

sql.py: DbConn.run_query(): Pass input query to get_cur_query()

sql.py: get_cur_query() and _add_cursor_info(): Support input_query param that will be used if the raw query is None. Pass input_query in DbConn.execute().

sql.py: DbConn.run_query(): Check that query != None

bin/map: out_is_db: Only rollback() and close() out_db if it was connected

sql.py: DbConn: Added connected()

sql.py: Wrapped calls to get_cur_query() that are used as strings in str(), because get_cur_query() can return None