Fixed requires with __PATH__

This because the gateway had issues with an autoloader or such in
WHMCS. Don't know the exact cause, but this fixed it.

src/mollie/callback.php

@@ -4,8 +4,8 @@
  *	Setting requirements and includes
  *
  */
-require_once '../../../init.php';
-require_once 'vendor/Mollie/src/Mollie/API/Autoloader.php';
+require_once __DIR__ . '/../../../init.php';
+require_once __DIR__ . '/vendor/Mollie/src/Mollie/API/Autoloader.php';
 
 $whmcs->load_function('gateway');
 $whmcs->load_function('invoice');

src/mollie/mollie.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once 'vendor/Mollie/src/Mollie/API/Autoloader.php';
+require_once __DIR__ . '/vendor/Mollie/src/Mollie/API/Autoloader.php';
 
 function mollie_config() {
     return array(

src/molliebanktransfer.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once 'mollie/mollie.php';
+require_once __DIR__ . '/mollie/mollie.php';
 
 function molliebanktransfer_config() {
 	$config = mollie_config();

src/molliebelfius.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once 'mollie/mollie.php';
+require_once __DIR__ . '/mollie/mollie.php';
 
 function molliebelfius_config() {
 	$config = mollie_config();

src/molliebitcoin.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once 'mollie/mollie.php';
+require_once __DIR__ . '/mollie/mollie.php';
 
 function molliebitcoin_config() {
 	$config = mollie_config();

src/molliedirectdebit.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once 'mollie/mollie.php';
+require_once __DIR__ . '/mollie/mollie.php';
 
 function molliedirectdebit_config() {
 	$config = mollie_config();

src/mollieideal.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once 'mollie/mollie.php';
+require_once __DIR__ . '/mollie/mollie.php';
 
 function mollieideal_config() {
 	$config = mollie_config();

src/molliemistercash.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once 'mollie/mollie.php';
+require_once __DIR__ . '/mollie/mollie.php';
 
 function molliemistercash_config() {
 	$config = mollie_config();

src/molliepaypal.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once 'mollie/mollie.php';
+require_once __DIR__ . '/mollie/mollie.php';
 
 function molliepaypal_config() {
 	$config = mollie_config();

src/molliepaysafecard.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once 'mollie/mollie.php';
+require_once __DIR__ . '/mollie/mollie.php';
 
 function molliepaysafecard_config() {
 	$config = mollie_config();

src/molliesofort.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once 'mollie/mollie.php';
+require_once __DIR__ . '/mollie/mollie.php';
 
 function molliesofort_config() {
 	$config = mollie_config();