Added a getInner method for retrieving the inner exception

Signed-off-by: Dejan Geci <dejan.geci@gmail.com>

laravel/database/exception.php

@@ -24,6 +24,16 @@ public function __construct($sql, $bindings, \Exception $inner)
 		$this->setMessage($sql, $bindings);
 	}
 
+	/**
+	 * Get the inner exception.
+	 *
+	 * @return Exception
+	 */
+	public function getInner()
+	{
+		return $this->inner;
+	}
+
 	/**
 	 * Set the exception message to include the SQL and bindings.
 	 *