Add `list --sort time` test reproducing Gianluca's bug.
drwxr-xr-x - .be
-rw-r--r-- 60 .gitignore
-rw-r--r-- 751 AUTHORS
-rw-r--r-- 17987 COPYING
-rw-r--r-- 2642 Makefile
-rw-r--r-- 4498 NEWS
-rw-r--r-- 2319 README
-rwxr-xr-x 1115 be
drwxr-xr-x - doc
drwxr-xr-x - interfaces
drwxr-xr-x - libbe
drwxr-xr-x - misc
-rwxr-xr-x 5714 release.py
-rwxr-xr-x 792 setup.py
-rw-r--r-- 4173 test.py
-rwxr-xr-x 952 test_upgrade.py
-rwxr-xr-x 4825 test_usage.sh
-rwxr-xr-x 22749 update_copyright.py