Renamed some stuff, courtesy of sensiolabs.

app/Generator/Chart/Account/AccountChartGeneratorInterface.php

@@ -1,4 +1,11 @@
 <?php
+/**
+ * AccountChartGeneratorInterface.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\Generator\Chart\Account;
 
@@ -7,11 +14,11 @@ use FireflyIII\Models\Account;
 use Illuminate\Support\Collection;
 
 /**
- * Interface AccountChartGenerator
+ * Interface AccountChartGeneratorInterface
  *
  * @package FireflyIII\Generator\Chart\Account
  */
-interface AccountChartGenerator
+interface AccountChartGeneratorInterface
 {
 
     /**

app/Generator/Chart/Account/ChartJsAccountChartGenerator.php

@@ -12,7 +12,7 @@ use Steam;
  *
  * @package FireflyIII\Generator\Chart\Account
  */
-class ChartJsAccountChartGenerator implements AccountChartGenerator
+class ChartJsAccountChartGenerator implements AccountChartGeneratorInterface
 {
 
     /**

app/Generator/Chart/Bill/BillChartGeneratorInterface.php

@@ -1,4 +1,12 @@
 <?php
+/**
+ * BillChartGeneratorInterface.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\Generator\Chart\Bill;
 
 
@@ -6,11 +14,11 @@ use FireflyIII\Models\Bill;
 use Illuminate\Support\Collection;
 
 /**
- * Interface BillChartGenerator
+ * Interface BillChartGeneratorInterface
  *
  * @package FireflyIII\Generator\Chart\Bill
  */
-interface BillChartGenerator
+interface BillChartGeneratorInterface
 {
 
     /**

app/Generator/Chart/Bill/ChartJsBillChartGenerator.php

@@ -1,4 +1,11 @@
 <?php
+/**
+ * ChartJsBillChartGenerator.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\Generator\Chart\Bill;
 
@@ -11,7 +18,7 @@ use Illuminate\Support\Collection;
  *
  * @package FireflyIII\Generator\Chart\Bill
  */
-class ChartJsBillChartGenerator implements BillChartGenerator
+class ChartJsBillChartGenerator implements BillChartGeneratorInterface
 {
 
     /**

app/Generator/Chart/Budget/BudgetChartGeneratorInterface.php

@@ -1,15 +1,22 @@
 <?php
+/**
+ * BudgetChartGeneratorInterface.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\Generator\Chart\Budget;
 
 use Illuminate\Support\Collection;
 
 /**
- * Interface BudgetChartGenerator
+ * Interface BudgetChartGeneratorInterface
  *
  * @package FireflyIII\Generator\Chart\Budget
  */
-interface BudgetChartGenerator
+interface BudgetChartGeneratorInterface
 {
     /**
      * @param Collection $entries

app/Generator/Chart/Budget/ChartJsBudgetChartGenerator.php

@@ -12,7 +12,7 @@ use Preferences;
  *
  * @package FireflyIII\Generator\Chart\Budget
  */
-class ChartJsBudgetChartGenerator implements BudgetChartGenerator
+class ChartJsBudgetChartGenerator implements BudgetChartGeneratorInterface
 {
 
     /**

app/Generator/Chart/Category/CategoryChartGeneratorInterface.php

@@ -1,15 +1,22 @@
 <?php
+/**
+ * CategoryChartGeneratorInterface.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\Generator\Chart\Category;
 
 use Illuminate\Support\Collection;
 
 /**
- * Interface CategoryChartGenerator
+ * Interface CategoryChartGeneratorInterface
  *
  * @package FireflyIII\Generator\Chart\Category
  */
-interface CategoryChartGenerator
+interface CategoryChartGeneratorInterface
 {
 
     /**

app/Generator/Chart/Category/ChartJsCategoryChartGenerator.php

@@ -10,7 +10,7 @@ use Illuminate\Support\Collection;
  *
  * @package FireflyIII\Generator\Chart\Category
  */
-class ChartJsCategoryChartGenerator implements CategoryChartGenerator
+class ChartJsCategoryChartGenerator implements CategoryChartGeneratorInterface
 {
 
     /**

app/Generator/Chart/PiggyBank/ChartJsPiggyBankChartGenerator.php

@@ -11,7 +11,7 @@ use Illuminate\Support\Collection;
  *
  * @package FireflyIII\Generator\Chart\PiggyBank
  */
-class ChartJsPiggyBankChartGenerator implements PiggyBankChartGenerator
+class ChartJsPiggyBankChartGenerator implements PiggyBankChartGeneratorInterface
 {
 
     /**

app/Generator/Chart/PiggyBank/PiggyBankChartGenerator.php

@@ -1,20 +0,0 @@
-<?php
-
-namespace FireflyIII\Generator\Chart\PiggyBank;
-
-use Illuminate\Support\Collection;
-
-/**
- * Interface PiggyBankChartGenerator
- *
- * @package FireflyIII\Generator\Chart\PiggyBank
- */
-interface PiggyBankChartGenerator
-{
-    /**
-     * @param Collection $set
-     *
-     * @return array
-     */
-    public function history(Collection $set);
-}

app/Generator/Chart/PiggyBank/PiggyBankChartGeneratorInterface.php

@@ -0,0 +1,27 @@
+<?php
+/**
+ * PiggyBankChartGenerator.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\Generator\Chart\PiggyBank;
+
+use Illuminate\Support\Collection;
+
+/**
+ * Interface PiggyBankChartGeneratorInterface
+ *
+ * @package FireflyIII\Generator\Chart\PiggyBank
+ */
+interface PiggyBankChartGeneratorInterface
+{
+    /**
+     * @param Collection $set
+     *
+     * @return array
+     */
+    public function history(Collection $set);
+}

app/Generator/Chart/Report/ReportChartGeneratorInterface.php

@@ -1,15 +1,22 @@
 <?php
+/**
+ * ReportChartGenerator.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\Generator\Chart\Report;
 
 use Illuminate\Support\Collection;
 
 /**
- * Interface ReportChartGenerator
+ * Interface ReportChartGeneratorInterface
  *
  * @package FireflyIII\Generator\Chart\Report
  */
-interface ReportChartGenerator
+interface ReportChartGeneratorInterface
 {
 
     /**