Remove remains of html5validator

.travis.yml

@@ -1,18 +1,16 @@
 sudo: false
 dist: trusty
-language: java
-jdk:
-  # Install JDK8 for html5 validator.
-  - oraclejdk8
+language: node_js
+node_js:
+  - "6"
 env:
-  - NODE_VERSION="6.11.2" PHANTOMJS_VERSION="2.1.1" PATH="$PWD/travis_phantomjs/phantomjs-$PHANTOMJS_VERSION-linux-x86_64/bin:$PATH"
+  - PHANTOMJS_VERSION="2.1.1" PATH="$PWD/travis_phantomjs/phantomjs-$PHANTOMJS_VERSION-linux-x86_64/bin:$PATH"
 cache:
   directories:
     - travis_phantomjs
 notifications:
   email: false
 before_install: |
-  nvm install $NODE_VERSION
   # Make sure cached PhantomJS is up to date
   if [ $(phantomjs --version) != $PHANTOMJS_VERSION ]; then
     rm -rf $PWD/travis_phantomjs
@@ -27,7 +25,6 @@ install:
   # Disable the spinner; it looks bad on Travis.
   - npm config set spin false
   - npm install
-  - pip install --user html5validator
   # Unclear why we have to install this separately, since it's in package.json,
   # but Travis fails without it.
   - npm install -g cssbeautify-cli