Setup the html check in circleci (#719)

* Setup the html check in circleci

as jenkins is broken I've setup the rake test in circle ci

it's super fast thanks to caching the bundle install results

.circleci/config.yml

@@ -0,0 +1,35 @@
+# Ruby CircleCI 2.0 configuration file
+#
+# Check https://circleci.com/docs/2.0/language-ruby/ for more details
+#
+version: 2
+jobs:
+  build:
+    docker:
+      # specify the version you desire here
+       - image: circleci/ruby:2.4.1-node-browsers
+
+    working_directory: ~/repo
+
+    steps:
+      - checkout
+
+      # Download and cache dependencies
+      - restore_cache:
+          keys:
+          - v1-dependencies-{{ checksum "Gemfile.lock" }}
+          # fallback to using the latest cache if no exact match is found
+          - v1-dependencies-
+
+      - run:
+          name: install dependencies
+          command: |
+            bundle install --jobs=4 --retry=3 --path vendor/bundle
+
+      - save_cache:
+          paths:
+            - ./vendor/bundle
+          key: v1-dependencies-{{ checksum "Gemfile.lock" }}
+
+      # Run the test/html checker
+      - run: bundle exec rake test

Gemfile

@@ -4,4 +4,5 @@ gem "github-pages", group: :jekyll_plugins
 gem "jekyll-include-cache", "~> 0.1"
 gem "nokogiri", "= 1.7.2"
 gem "html-proofer"
+gem "rake"
 

Gemfile.lock

@@ -201,6 +201,7 @@ GEM
     pathutil (0.16.0)
       forwardable-extended (~> 2.6)
     public_suffix (2.0.5)
+    rake (12.0.0)
     rb-fsevent (0.10.2)
     rb-inotify (0.9.10)
       ffi (>= 0.5.0, < 2)
@@ -232,6 +233,7 @@ DEPENDENCIES
   html-proofer
   jekyll-include-cache (~> 0.1)
   nokogiri (= 1.7.2)
+  rake
 
 BUNDLED WITH
    1.14.6

_config.yml

@@ -60,6 +60,7 @@ exclude:
   - Jenkinsfile
   - repos/*.html
   - repos/*.md
+  - vendor/
 
 repository:
   istio/istio.github.io