minor #6414 stick to Sphinx 1.3.x for the moment (xabbuh)

This PR was merged into the 2.3 branch.

Discussion
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stick to Sphinx 1.3.x for the moment

Commits
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75d83f1 stick to Sphinx 1.3.x for the moment

Author: xabbuh

.travis.yml

@@ -9,7 +9,7 @@ cache:
         - $HOME/.cache/pip
         - _build
 
-install: pip install sphinx~=1.3 git+https://github.com/fabpot/sphinx-php.git
+install: pip install sphinx~=1.3.0 git+https://github.com/fabpot/sphinx-php.git
 
 script: sphinx-build -nW -b html -d _build/doctrees . _build/html