Convert readthedocs links for their .org -> .io migration for hosted projects

As per [their blog post of the 27th April](https://blog.readthedocs.com/securing-subdomains/) ‘Securing subdomains’:

> Starting today, Read the Docs will start hosting projects from subdomains on the domain readthedocs.io, instead of on readthedocs.org. This change addresses some security concerns around site cookies while hosting user generated data on the same domain as our dashboard.

Test Plan: Manually visited all the links I’ve modified.

docs/scenarios/ci.rst

@@ -35,7 +35,7 @@ automate the compile/test cycle to validate code changes.
 Tox
 ---
 
-`tox <http://tox.readthedocs.org/en/latest/>`_ is an automation tool providing
+`tox <https://tox.readthedocs.io/en/latest/>`_ is an automation tool providing
 packaging, testing and deployment of Python software right from the console or
 CI server. It is a generic virtualenv management and test command line tool
 which provides the following features:

docs/scenarios/clibs.rst

@@ -4,7 +4,7 @@ Interfacing with C/C++ Libraries
 C Foreign Function Interface
 ----------------------------
 
-`CFFI <https://cffi.readthedocs.org/en/latest/>`_ provides a simple to use
+`CFFI <https://cffi.readthedocs.io/en/latest/>`_ provides a simple to use
 mechanism for interfacing with C from both CPython and PyPy. It supports two
 modes: an inline ABI compatibility mode (example provided below), which allows
 you to dynamically load and run functions from executable modules (essentially

docs/scenarios/db.rst

@@ -60,11 +60,11 @@ peewee
 `peewee <http://docs.peewee-orm.com/en/latest/>`_ is another ORM with a focus
 on being lightweight with support for Python 2.6+ and 3.2+ which supports
 SQLite, MySQL and Postgres by default. The
-`model layer <https://peewee.readthedocs.org/en/latest/peewee/quickstart.html#model-definition>`_
+`model layer <https://peewee.readthedocs.io/en/latest/peewee/quickstart.html#model-definition>`_
 is similar to that of the Django ORM and it has
-`SQL-like methods <https://peewee.readthedocs.org/en/latest/peewee/quickstart.html#retrieving-data>`_
+`SQL-like methods <https://peewee.readthedocs.io/en/latest/peewee/quickstart.html#retrieving-data>`_
 to query data. While SQLite, MySQL and Postgres are supported out-of-the-box,
-there is a `collection of add-ons <https://peewee.readthedocs.org/en/latest/peewee/playhouse.html#playhouse>`_
+there is a `collection of add-ons <https://peewee.readthedocs.io/en/latest/peewee/playhouse.html#playhouse>`_
 available.
 
 PonyORM

docs/scenarios/gui.rst

@@ -28,7 +28,7 @@ applications be ported from PyGTK to PyGObject.
 PyGObject aka (PyGi)
 --------------------
 `PyGObject <https://wiki.gnome.org/Projects/PyGObject>`_ provides Python bindings, which gives access to the entire GNOME software platform.
-It is fully compatible with GTK+ 3. Here is a tutorial to get started with `Python GTK+ 3 Tutorial <http://python-gtk-3-tutorial.readthedocs.org/en/latest/>`_.
+It is fully compatible with GTK+ 3. Here is a tutorial to get started with `Python GTK+ 3 Tutorial <https://python-gtk-3-tutorial.readthedocs.io/en/latest/>`_.
 
 `API Reference <http://lazka.github.io/pgi-docs/>`_
 

docs/scenarios/imaging.rst

@@ -24,7 +24,7 @@ Installation
 
 Before installing Pillow, you'll have to install Pillow's prerequisites. Find
 the instructions for your platform in the
-`Pillow installation instructions <https://pillow.readthedocs.org/en/3.0.0/installation.html>`_.
+`Pillow installation instructions <https://pillow.readthedocs.io/en/3.0.0/installation.html>`_.
 
 After that, it's straightforward:
 
@@ -57,7 +57,7 @@ Example
     exif_data
 
 There are more examples of the Pillow library in the
-`Pillow tutorial <http://pillow.readthedocs.org/en/3.0.x/handbook/tutorial.html>`_.
+`Pillow tutorial <https://pillow.readthedocs.io/en/3.0.x/handbook/tutorial.html>`_.
 
 
 OpenSource Computer Vision
@@ -104,4 +104,4 @@ Example
 
 There are more Python-implemented examples of OpenCV in this `collection of
 tutorials
-<http://opencv-python-tutroals.readthedocs.org/en/latest/py_tutorials/py_tutorials.html>`_.
+<https://opencv-python-tutroals.readthedocs.io/en/latest/py_tutorials/py_tutorials.html>`_.

docs/scenarios/json.rst

@@ -47,7 +47,7 @@ simplejson
 
 The JSON library was added to Python in version 2.6.
 If you're using an earlier version of Python, the
-`simplejson <https://simplejson.readthedocs.org/en/latest/>`_ library is
+`simplejson <https://simplejson.readthedocs.io/en/latest/>`_ library is
 available via PyPI.
 
 simplejson mimics the json standard library. It is available so that developers

docs/scenarios/web.rst

@@ -154,7 +154,7 @@ Gunicorn is the recommended choice for new Python web applications today.
 Waitress
 --------
 
-`Waitress <http://waitress.readthedocs.org>`_ is a pure-python WSGI server
+`Waitress <https://waitress.readthedocs.io>`_ is a pure-python WSGI server
 that claims "very acceptable performance". Its documentation is not very
 detailed, but it does offer some nice functionality that Gunicorn doesn't have
 (e.g. HTTP request buffering).
@@ -166,18 +166,18 @@ Waitress is gaining popularity within the Python web development community.
 uWSGI
 -----
 
-`uWSGI <https://uwsgi-docs.readthedocs.org>`_ is a full stack for building
+`uWSGI <https://uwsgi-docs.readthedocs.io>`_ is a full stack for building
 hosting services.  In addition to process management, process monitoring,
 and other functionality, uWSGI acts as an application server for various
 programming languages and protocols - including Python and WSGI. uWSGI can
 either be run as a stand-alone web router, or be run behind a full web
 server (such as Nginx or Apache).  In the latter case, a web server can
 configure uWSGI and an application's operation over the
-`uwsgi protocol <https://uwsgi-docs.readthedocs.org/en/latest/Protocol.html>`_.
+`uwsgi protocol <https://uwsgi-docs.readthedocs.io/en/latest/Protocol.html>`_.
 uWSGI's web server support allows for dynamically configuring
 Python, passing environment variables and further tuning.  For full details,
 see `uWSGI magic
-variables <https://uwsgi-docs.readthedocs.org/en/latest/Vars.html>`_.
+variables <https://uwsgi-docs.readthedocs.io/en/latest/Vars.html>`_.
 
 I do not recommend using uWSGI unless you know why you need it.
 
@@ -393,10 +393,10 @@ Jinja2 is the recommended templating library for new Python web applications.
 Chameleon
 ---------
 
-`Chameleon <https://chameleon.readthedocs.org/>`_ Page Templates are an HTML/XML template
+`Chameleon <https://chameleon.readthedocs.io/>`_ Page Templates are an HTML/XML template
 engine implementation of the `Template Attribute Language (TAL) <http://en.wikipedia.org/wiki/Template_Attribute_Language>`_,
-`TAL Expression Syntax (TALES) <http://chameleon.readthedocs.org/en/latest/reference.html#expressions-tales>`_,
-and `Macro Expansion TAL (Metal) <http://chameleon.readthedocs.org/en/latest/reference.html#macros-metal>`_ syntaxes.
+`TAL Expression Syntax (TALES) <https://chameleon.readthedocs.io/en/latest/reference.html#expressions-tales>`_,
+and `Macro Expansion TAL (Metal) <https://chameleon.readthedocs.io/en/latest/reference.html#macros-metal>`_ syntaxes.
 
 Chameleon is available for Python 2.5 and up (including 3.x and pypy), and
 is commonly used by the `Pyramid Framework <http://trypyramid.com>`_.