Add forked Maatkit tools in bin/ and their tests in t/.

t/pt-query-digest/report_histogram.t

@@ -0,0 +1,34 @@
+#!/usr/bin/env perl
+
+BEGIN {
+   die "The PERCONA_TOOLKIT_BRANCH environment variable is not set.\n"
+      unless $ENV{PERCONA_TOOLKIT_BRANCH} && -d $ENV{PERCONA_TOOLKIT_BRANCH};
+   unshift @INC, "$ENV{PERCONA_TOOLKIT_BRANCH}/lib";
+};
+
+use strict;
+use warnings FATAL => 'all';
+use English qw(-no_match_vars);
+use Test::More tests => 1;
+
+use MaatkitTest;
+shift @INC;  # our unshift (above)
+shift @INC;  # MaatkitTest's unshift
+require "$trunk/bin/pt-query-digest";
+
+my @args   = ('--report-format', 'query_report,profile', qw(--limit 10));
+my $sample = "$trunk/t/lib/samples/slowlogs/";
+
+ok(
+   no_diff(
+      sub { mk_query_digest::main(@args, qw(--report-histogram Lock_time),
+         qw(--order-by Lock_time:sum), $sample.'slow034.txt') },
+      "t/pt-query-digest/samples/slow034-order-by-Locktime-sum-with-Locktime-distro.txt",
+   ),
+   '--report-histogram Lock_time'
+);
+
+# #############################################################################
+# Done.
+# #############################################################################
+exit;