Moved charts to separate generators.

app/Generator/Chart/Bill/BillChartGenerator.php

@@ -0,0 +1,32 @@
+<?php
+namespace FireflyIII\Generator\Chart\Bill;
+
+
+use FireflyIII\Models\Bill;
+use Illuminate\Support\Collection;
+
+/**
+ * Interface BillChartGenerator
+ *
+ * @package FireflyIII\Generator\Chart\Bill
+ */
+interface BillChartGenerator
+{
+
+    /**
+     * @param Bill       $bill
+     * @param Collection $entries
+     *
+     * @return array
+     */
+    public function single(Bill $bill, Collection $entries);
+
+    /**
+     * @param Collection $paid
+     * @param Collection $unpaid
+     *
+     * @return array
+     */
+    public function frontpage(Collection $paid, Collection $unpaid);
+
+}