Shutdown Doc worker when it is not considered as available in Redis #831 (#856)

* Shutdown Doc worker when it is not considered as available in Redis
* Use isAffirmative for GRIST_MANAGED_WORKERS
* Upgrade Sinon for the tests
* Run Smoke test with pages in English
* Add logic in /status endpoint

buildtools/webpack.config.js

@@ -56,6 +56,7 @@ module.exports = {
     ],
     fallback: {
       'path': require.resolve("path-browserify"),
+      'process': require.resolve("process/browser"),
     },
   },
   module: {
@@ -79,7 +80,7 @@ module.exports = {
   plugins: [
     // Some modules assume presence of Buffer and process.
     new ProvidePlugin({
-      process: 'process/browser',
+      process: 'process',
       Buffer: ['buffer', 'Buffer']
     }),
     // To strip all locales except “en”