Lock grunt-cli version to 1.2.0.

.circleci/config.yml

@@ -34,7 +34,7 @@ jobs:
           - v2-dependencies-targetchromium-{{ checksum "omega-target-chromium-extension/package.json" }}
           - v2-dependencies-targetchromium
 
-      - run: sudo npm install -g grunt-cli bower web-ext json
+      - run: sudo npm install -g grunt-cli@1.2.0 bower web-ext json
       - run: (cd omega-build && npm run deps)
 
       - save_cache:

README.md

@@ -101,7 +101,7 @@ To build the project:
 
     # Install node and npm first (make sure npm --version > 2.0), then:
     
-    sudo npm install -g grunt-cli bower
+    sudo npm install -g grunt-cli@1.2.0 bower
     # In the project folder:
     cd omega-build
     npm run deps # This runs npm install in every module.