Add Yarn lockfile, travis & appveyor support.

Author: STRML

.travis.yml

@@ -1,10 +1,22 @@
 language: node_js
 node_js:
-  - "0.10"
-  - "0.12"
   - "4"
   - "6"
   - "7"
+before_install:
+  # Repo for newer Node.js versions
+  - curl -sL https://deb.nodesource.com/setup_6.x | sudo -E bash -
+  # Repo for Yarn
+  - sudo apt-key adv --keyserver pgp.mit.edu --recv D101F7899D41F3C3
+  - echo "deb http://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list
+  - sudo apt-get update -qq
+  - sudo apt-get install -y -qq yarn
+install:
+  - node --version
+  - yarn install
+cache:
+  directories:
+  - $HOME/.yarn-cache
 before_script:
   - export CHROME_BIN=chromium-browser
   - export DISPLAY=:99.0

appveyor.yml

@@ -1,13 +1,25 @@
 # https://www.appveyor.com/docs/appveyor-yml/
 
+environment:
+  matrix:
+    - node_version: "7"
+    - node_version: "6"
+    - node_version: "4"
+
 cache:
   - node_modules
 
 environment:
   IE_BIN: "%PROGRAMFILES%\\Internet Explorer\\iexplorer.exe"
 
 install:
-  - npm install
+  - ps: Install-Product node $env:node_version
+  - choco install -i yarn
+  - refreshenv
+  - yarn install
+
+cache:
+ - "%LOCALAPPDATA%/Yarn"
 
 test_script:
   - npm run test-ie