Switch to using the sdist for hiredis (pypi#4584)

Author: dstufft

Dockerfile

@@ -108,7 +108,8 @@ RUN set -x \
 RUN set -x \
     && PIP_EXTRA_INDEX_URL=$THEME_REPO \
         pip --no-cache-dir --disable-pip-version-check \
-            install -r /tmp/requirements/deploy.txt \
+            install --no-binary hiredis \
+                    -r /tmp/requirements/deploy.txt \
                     -r /tmp/requirements/main.txt \
                     $(if [ "$DEVEL" = "yes" ]; then echo '-r /tmp/requirements/tests.txt'; fi) \
                     $(if [ "$THEME_REPO" != "" ]; then echo '-r /tmp/requirements/theme.txt'; fi) \