[Patch for help2man] make date and time format translatable

[Yasumichi Akahoshi]

 Thank you for development help2man.
 Because help2man give fixed format "%B %Y" to strftime, the date of the
last revision is outputted in order of month and year. But in Japan it
is not general. In Japan it is general to output in order year and
month.
 Therefor I suggest to make format translatable in following patch.
Please examine it.

diff -uNr help2man-1.39.2.org/help2man.PL help2man-1.39.2/help2man.PL
--- help2man-1.39.2.org/help2man.PL     2011-05-06 17:31:53.000000000 +0900
+++ help2man-1.39.2/help2man.PL 2011-05-06 17:32:24.000000000 +0900
@@ -331,7 +331,7 @@
 my $help_text   = get_option_value $ARGV[0], $help_option;
 $version_text ||= get_option_value $ARGV[0], $version_option;

-my $date = strftime "%B %Y", localtime;
+my $date = enc strftime _("%B %Y"), localtime;
 (my $program = $ARGV[0]) =~ s!.*/!!;
 my $package = $program;
 my $version;

--
Yasumichi Akahoshi
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