from qgis.core import *
from qgis.utils import *
import os, sys

QgsApplication.setPrefixPath("C:/OSGeo4W64/apps/qgis", True)
app = QApplication([], True)
QgsApplication.initQgis()

sys.path.append('C:/OSGEO4~1/apps/qgis/python/plugins')
from processing.core.Processing import Processing
Processing.initialize()
from processing.tools import *

layer1 = "path/to/point_shapefile.shp"
layer2 = "path/to/polygon_shapefile.shp"
result = "path/to/output_shapefile.shp"

general.runalg("qgis:joinattributesbylocation", layer1, layer2, u'intersects', 0, '', 1, result)