Update doc

.circleci/deploy.sh

@@ -68,4 +68,5 @@ deploy_doc "7a6c9fa" v4.7.0
 deploy_doc "9252a51" v4.8.0
 deploy_doc "1366172" v4.8.1
 deploy_doc "96d1cfb" v4.8.2
-deploy_doc "72aee83"  # v4.9.0 Latest stable release
+deploy_doc "72aee83" v4.9.0
\ No newline at end of file
+deploy_doc "bff1c71"  # v4.9.1 Latest stable release
\ No newline at end of file

docs/source/_static/js/custom.js

 // These two things need to be updated at each release for the version selector.
 // Last stable version
-const stableVersion = "v4.9.0"
+const stableVersion = "v4.9.1"
 // Dictionary doc folder to label. The last stable version should have an empty key.
 const versionMapping = {
     "master": "master",
-    "": "v4.9.0 (stable)",
+    "": "v4.9.0/v4.9.1 (stable)",
     "v4.8.2": "v4.8.0/v4.8.1/v4.8.2",
     "v4.7.0": "v4.7.0",
     "v4.6.0": "v4.6.0",