devel/py-retrying: Convert to USE_PYTHON=pep517

- Bump PORTREVISION for package change

devel/py-retrying/Makefile

 PORTNAME=	retrying
 PORTVERSION=	1.3.4
+PORTREVISION=	1
 CATEGORIES=	devel python
 MASTER_SITES=	PYPI
 PKGNAMEPREFIX=	${PYTHON_PKGNAMEPREFIX}
@@ -11,10 +12,12 @@ WWW=		https://github.com/rholder/retrying
 LICENSE=	APACHE20
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
+BUILD_DEPENDS=	${PYTHON_PKGNAMEPREFIX}setuptools>=0:devel/py-setuptools@${PY_FLAVOR} \
+		${PYTHON_PKGNAMEPREFIX}wheel>=0:devel/py-wheel@${PY_FLAVOR}
 RUN_DEPENDS=	${PYTHON_PKGNAMEPREFIX}six>=1.7.0:devel/py-six@${PY_FLAVOR}
 
 USES=		python
-USE_PYTHON=	autoplist concurrent distutils
+USE_PYTHON=	autoplist concurrent pep517
 
 NO_ARCH=	yes