Bump Clownfish::CFC depedency

Make sure that CPAN Testers use Clownfish::CFC 0.5.1.
diff --git a/perl/Build.PL b/perl/Build.PL
index 34d438e..84533c8 100644
--- a/perl/Build.PL
+++ b/perl/Build.PL
@@ -55,7 +55,7 @@
         'ExtUtils::ParseXS'  => 2.18,
         'Devel::PPPort'      => 3.14,
         'Clownfish'          => 0.005000,
-        'Clownfish::CFC'     => 0.005000,
+        'Clownfish::CFC'     => 0.005001,
     },
     meta_merge => { keywords => [qw( search lucy lucene )], },
     meta_add   => {