Update sphinx from 1.7.0 to 1.7.1

requirements/docs.txt

@@ -7,9 +7,9 @@ Pygments==2.2.0 \
     --hash=sha256:78f3f434bcc5d6ee09020f92ba487f95ba50f1e3ef83ae96b9d5ffa1bab25c5d \
     --hash=sha256:dbae1046def0efb574852fab9e90209b23f556367b5a320c0bcb871c77c3e8cc
 # Sphinx is required by sphinxcontrib-httpdomain
-Sphinx==1.7.0 \
-    --hash=sha256:a0b16810d1d1413dec006ce2b08b5c895b2aaa7dce18d579d3ef79c03d461b22 \
-    --hash=sha256:278b7923f3f4ed2a1d1359f0ae94d89ac90ddd4189e8362f4b4d3baa2afe6b4a
+Sphinx==1.7.1 \
+    --hash=sha256:41ae26acc6130ccf6ed47e5cca73742b80d55a134f0ab897c479bba8d3640b8e \
+    --hash=sha256:da987de5fcca21a4acc7f67a86a363039e67ac3e8827161e61b91deb131c0ee8
 # alabaster is required by Sphinx
 alabaster==0.7.10 \
     --hash=sha256:2eef172f44e8d301d25aff8068fddd65f767a3f04b5f15b0f4922f113aa1c732 \