Update CHANGES.rst [skip travis]
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CHANGES.rst
CHANGES.rst
-The ``repo2docker`` changelog has been moved to https://repo2docker.readthedocs.io/en/latest/changelog.html
+The ``repo2docker`` changelog has been moved. It can be viewed online at https://repo2docker.readthedocs.io/en/latest/changelog.html. In the ``repo2docker`` repository, the changelog is located at ``docs/source/changelog.rst``.

Update CHANGES.rst [skip travis]