perl: bump the required Perl version to 5.8 from 5.6.[21]

diff --git a/git-send-email.perl b/git-send-email.perl
index 6dab3bf6a74bb52c7294e33dbac5bf87b51a9fdf..314e59e7a9f14d8bf1106cf5f5dd73da65f30905 100755 (executable)
--- a/git-send-email.perl
+++ b/git-send-email.perl
@@ -16,6 +16,7 @@
 #    and second line is the subject of the message.
 #
 
+use 5.008;
 use strict;
 use warnings;
 use Term::ReadLine;