ctime no longer accurate in package-list.pl

[jdreed]

package-list.pl was updated to conditionally look at the .deb's ctime, and use that to determine if if it was "time" to move it from proposed into production. Since packages can now spend an indeterminate amount of time in -development, this is no longer accurate. I can change package-list.pl to use mtime instead if reprepro can be convinced to "touch" each .deb it acts upon. I don't know if that's easy to accomplish or not.