Replace Carbon type hinting by CarbonInterface

Author: EraTorr

README.md

@@ -380,7 +380,7 @@ Almost every configuration value can be overrided dynamically by methods.
 - getSerialNumber() - returns formatted serial number
 
 #### Date
-- date(Carbon)
+- date(CarbonInterface)
 - dateFormat(string) - Carbon format of date
 - payUntilDays(int) - Days payment due since invoice issued
 - getDate() - returns formatted date

src/Traits/DateFormatter.php

@@ -2,15 +2,15 @@
 
 namespace LaravelDaily\Invoices\Traits;
 
-use Carbon\Carbon;
+use Carbon\CarbonInterface;
 
 /**
  * Trait DateFormatter
  */
 trait DateFormatter
 {
     /**
-     * @var Carbon
+     * @var CarbonInterface
      */
     public $date;
 
@@ -25,10 +25,10 @@ trait DateFormatter
     public $pay_until_days;
 
     /**
-     * @param Carbon $date
+     * @param CarbonInterface $date
      * @return $this
      */
-    public function date(Carbon $date)
+    public function date(CarbonInterface $date)
     {
         $this->date = $date;