Log Message:
py-cairo: update to 1.19.1.

1.19.1 - 2020-02-16
-------------------

* docs: Add moderngl in the integration section. :pr:`174` (:user:`Einar Forselv \ 
<einarf>`)
* Support os.PathLike with PyPy3 >= 7.3.0

1.19.0 - 2020-01-23
-------------------

* Python 2 is no longer supported :pr:`172`
* Add machine-readable license statement :pr:`158` (:user:`Maxim Ivanov \ 
<ulidtko>`)
* travis-ci: Manually set sysroot so correct SDK is used (:user:`Stuart Axon \ 
<stuaxo>`)
* Support Python 3.8 on Windows (because of DLL lookup changes)
* Fix wrong type for set_dash() offset parameter in the docs/types.