New export functionality.

app/Export/Exporter/ExporterInterface.php

@@ -0,0 +1,41 @@
+<?php
+/**
+ * ExporterInterface.php
+ * Copyright (C) 2016 Sander Dorigo
+ *
+ * This software may be modified and distributed under the terms
+ * of the MIT license.  See the LICENSE file for details.
+ */
+
+namespace FireflyIII\Export\Exporter;
+use Illuminate\Support\Collection;
+
+/**
+ * Interface ExporterInterface
+ *
+ * @package FireflyIII\Export\Exporter
+ */
+interface ExporterInterface
+{
+    /**
+     * @return Collection
+     */
+    public function getEntries();
+
+    /**
+     *
+     */
+    public function run();
+
+    /**
+     * @param Collection $entries
+     *
+     */
+    public function setEntries(Collection $entries);
+
+    /**
+     * @return string
+     */
+    public function getFileName();
+
+}