* src/getargs.c: Die on `-r'/`--raw'.
* src/lex.c (parse_percent_token): Die on `%raw'.
* src/reader.c (output_token_defines): Suppress call to `raw_flag'.
* tests/calc.at: Suppress test with option `--raw'.
(stringappend): Be just like strcat but allocate.
(base_names): Eve out from open_files.
Try to simplify the rather hairy computation of base_name and
short_base_name.
(open_files): Use it.
* tests/suite.at (Checking output file names): New test.
