add timestamp.pl

scripts/timestamp.pl

+#!/usr/bin/perl
+
+# add timestamp to stdin (for long-running commands or with tail), e.g.
+# tail -f logfile | timestamp.pl
+use POSIX qw(strftime);
+while (<>) {
+	my $date = strftime "[%Y-%m-%d %H:%M:%S]", localtime;
+	print "$date $_";
+}