* tests/bench-slope.c (STR, STR2): New.
(cvs_mode): New.
(num_measurement_repetitions): New.  Replace use of
NUM_MEASUREMENT_REPETITIONS by this.
(current_section_name, current_algo_name, current_mode_name): New.
(bench_print_result_csv): New.
(bench_print_result_std): Rename from bench_print_result.
(bench_print_result): New. Divert depending on CSV_MODE.
(bench_print_header, bench_print_footer): take care of CSV_MODE.
(bench_print_algo, bench_print_mode): New.  Use them instead of
explicit printfs.
(main): Add options --csv and --repetitions.