Use Sphinx extlinks

I really really like the new lint/warn pass.  Thanks to everyone who helped make it!

hypothesis-python/docs/changes.rst

@@ -4,7 +4,7 @@ Changelog
 
 This is a record of all past Hypothesis releases and what went into them,
 in reverse chronological order. All previous releases should still be available
-on `PyPI <https://pypi.org/project/hypothesis/>`__.
+:pypi:`on PyPI <hypothesis>`.
 
 
 Hypothesis 6.x
@@ -5468,7 +5468,7 @@ This patch updates some docstrings, but has no runtime changes.
 
 This release adds ``exclude_min`` and ``exclude_max`` arguments to
 :func:`~hypothesis.strategies.floats`, so that you can easily generate values from
-`open or half-open intervals <https://en.wikipedia.org/wiki/Interval_(mathematics)>`_
+:wikipedia:`open or half-open intervals <Interval_(mathematics)>`
 (:issue:`1622`).
 
 .. _v4.4.6:

hypothesis-python/docs/community.rst

@@ -13,7 +13,7 @@ Feel free to use these to ask for help, provide feedback, or discuss anything re
 Hypothesis related at all.  If you post a question on Stack Overflow, please use the
 `python-hypothesis <https://stackoverflow.com/questions/tagged/python-hypothesis>`__ tag!
 
-Please note that `the Hypothesis code of conduct <https://github.com/HypothesisWorks/hypothesis/blob/master/CODE_OF_CONDUCT.rst>`_
+Please note that :gh-file:`the Hypothesis code of conduct <CODE_OF_CONDUCT.rst>`
 applies in all Hypothesis community spaces.
 
 If you would like to cite Hypothesis, please consider :gh-file:`our suggested citation <CITATION.cff>`.

hypothesis-python/docs/django.rst

@@ -41,8 +41,8 @@ a strategy for Django models:
 
 .. autofunction:: hypothesis.extra.django.from_model
 
-For example, using `the trivial django project we have for testing
-<https://github.com/HypothesisWorks/hypothesis/blob/master/hypothesis-python/tests/django/toystore/models.py>`_:
+For example, using :gh-file:`the trivial django project we have for testing
+<hypothesis-python/tests/django/toystore/models.py>`:
 
 .. code-block:: pycon
 

hypothesis-python/docs/quickstart.rst

@@ -9,9 +9,8 @@ Hypothesis.
 An example
 ----------
 
-Suppose we've written a `run length encoding
-<https://en.wikipedia.org/wiki/Run-length_encoding>`_ system and we want to test
-it out.
+Suppose we've written a :wikipedia:`run length encoding <Run-length_encoding>`
+system and we want to test it out.
 
 We have the following code which I took straight from the
 `Rosetta Code <https://rosettacode.org/wiki/Run-length_encoding>`_ wiki (OK, I

hypothesis-python/docs/supported.rst

@@ -98,6 +98,6 @@ Regularly verifying this
 ------------------------
 
 Everything mentioned above as explicitly supported is checked on every commit
-with `GitHub Actions <https://github.com/HypothesisWorks/hypothesis/actions>`__.
+with :gh-file:`GitHub Actions <actions>`.
 Our continuous delivery pipeline runs all of these checks before publishing
 each release, so when we say they're supported we really mean it.

hypothesis-python/docs/usage.rst

@@ -8,8 +8,7 @@ The only inclusion criterion right now is that if it's a Python library
 then it should be available on PyPI.
 
 You can find hundreds more from `the Hypothesis page at libraries.io
-<https://libraries.io/pypi/hypothesis>`_, and `thousands on GitHub
-<https://github.com/HypothesisWorks/hypothesis/network/dependents>`_.
+<https://libraries.io/pypi/hypothesis>`_, and :gh-file:`thousands on GitHub <network/dependents>`.
 Hypothesis has `over 100,000 downloads per week <https://pypistats.org/packages/hypothesis>`__,
 and was used by `more than 4% of Python users surveyed by the PSF in 2020
 <https://www.jetbrains.com/lp/python-developers-survey-2020/>`__.