use new-style tox.ini, add flake8-docstrings, add docstrings

incorporealcms/__init__.py

@@ -1,4 +1,4 @@
-"""create_app application factory function and similar things."""
+"""An application for running my Markdown-based sites."""
 import logging
 import os
 from logging.config import dictConfig
@@ -12,6 +12,7 @@ del get_versions
 
 
 def create_app(instance_path=None, test_config=None):
+    """Create the Flask app, with allowances for customizing path and test settings."""
     app = Flask(__name__, instance_relative_config=True, instance_path=instance_path)
 
     # if it doesn't already exist, create the instance folder