orderBy() accept uppercase order direction

Author: alexandre-butynski

Diff for: src/Jenssegers/Mongodb/Builder.php

@@ -268,7 +268,7 @@ public function distinct($column = false)
      */
     public function orderBy($column, $direction = 'asc')
     {
-        $this->orders[$column] = ($direction == 'asc' ? 1 : -1);
+        $this->orders[$column] = (strtolower($direction) == 'asc' ? 1 : -1);
 
         return $this;
     }

Diff for: tests/QueryTest.php

@@ -142,6 +142,9 @@ public function testOrder()
 		$user = User::whereNotNull('age')->orderBy('age', 'asc')->first();
 		$this->assertEquals(13, $user->age);
 
+		$user = User::whereNotNull('age')->orderBy('age', 'ASC')->first();
+		$this->assertEquals(13, $user->age);
+
 		$user = User::whereNotNull('age')->orderBy('age', 'desc')->first();
 		$this->assertEquals(37, $user->age);
 	}