sql_gen.py Join.to_str(), sql.py mk_select(): Combining conditions: Don't add newlines where not needed, so that output is less vertically spread out

sql_gen.py: is_safe_name(): Fixed bug where names starting with a digit were incorrectly considered safe

sql.py: put_table(): Separate temp table names from into table name with "_" instead of "-" so that quoting the table name will usually be unnecessary

sql.py: esc_name_by_module(): Remove unused param ignore_case

sql_gen.py: esc_name(): If is_safe_name(), just return name, to avoid escessive escaping in debug output for Redmine

sql_gen.py: is_safe_name(): Don't consider uppercase letters safe because they would cause inconsistent behavior in PostgreSQL if quoted vs. not quoted (only unquoted identifiers are case-insensitive)

sql.py: Removed no longer needed check_name()

sql.py: esc_name_by_module(): psycopg2: If ignore_case is set but name is unsafe, just escape it instead of raising an exception

sql_gen.py: Added is_safe_name()

sql.py: put_table(): col_ustr(): Removed no longer needed sql_gen.as_Col() because mapping and join_cols now ensure that their contents are sql_gen.Col objects