Added a test to the Epoch plugin.

t/Epoch.t

@@ -0,0 +1,19 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+use Test::More;
+use DDG::Test::Goodie;
+
+zci answer_type => 'epoch';
+zci is_cached => 1;
+
+ddg_goodie_test(
+        [qw( DDG::Goodie::Epoch )],
+        'epoch' => test_zci(
+            qr/Unix time/,
+        ),
+);
+
+done_testing;
+