doc generation for route is sensible to decorator orders

[masfaraud]

Hi, with Python 3.5.3, Flask 0.12.2 and flask-autodoc 0.1.2. It seems to me that doc won't generate for a route if the @auto.doc() decorator isn't immediately after the @app.route one. In the case of multiple decorators, this behavior is a little bit disturbing. This is not really a bug, but I think it should be mentioned in the documentation.