BLD: escape GH_TOKEN in build_docs

Author: jreback

ci/build_docs.sh

@@ -56,7 +56,8 @@ if [ x"$DOC_BUILD" != x"" ]; then
     git add --all .
     git commit -m "Version" --allow-empty
     git remote remove origin
-    git remote add origin "https://$GH_TOKEN@github.com/pandas-docs/pandas-docs-travis.git"
+    echo "https://${GH_TOKEN}@github.com/pandas-docs/pandas-docs-travis.git"
+    git remote add origin "https://${GH_TOKEN}@github.com/pandas-docs/pandas-docs-travis.git"
     git push origin gh-pages -f
 fi