Replace <> with <<>>

Replace <> with <<>>

The reason is that <> can be dangerous. From Perl documentation:

    Since the null filehandle uses the two argument form of "open" in
    perlfunc it interprets special characters, so if you have a script like
    this:

	while (<>) {
	    print;
	}

    and call it with "perl dangerous.pl 'rm -rfv *|'", it actually opens a
    pipe, executes the "rm" command and reads "rm"'s output from that pipe.
    If you want all items in @ARGV to be interpreted as file names, you can
    use the module "ARGV::readonly" from CPAN, or use the double diamond
    bracket:

	while (<<>>) {
	    print;
	}

    Using double angle brackets inside of a while causes the open to use
    the three argument form (with the second argument being "<"), so all
    arguments in "ARGV" are treated as literal filenames (including "-").
    (Note that for convenience, if you use "<<>>" and if @ARGV is empty, it
    will still read from the standard input.)