Add a sort command to test-string-list that reads lines from stdin,
stores them in a string_list and then sorts it. Use it in a simple
perf test script to measure the performance of string_list_sort().
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
