Fixed runtests.py problem from [3177] where it assumed you were running the...

def get_test_models():

    models = []

    for loc in MODEL_TESTS_DIR_NAME, REGRESSION_TESTS_DIR_NAME:

        for f in os.listdir(loc):

    for loc, dirpath in (MODEL_TESTS_DIR_NAME, MODEL_TEST_DIR), (REGRESSION_TESTS_DIR_NAME, REGRESSION_TEST_DIR):

        for f in os.listdir(dirpath):

            if f.startswith('__init__') or f.startswith('.') or f.startswith('sql'):

                continue

            models.append((loc, f))