Add Appveyor testing

README.markdown

@@ -1,7 +1,8 @@
 # [Jekyll](http://jekyllrb.com/)
 
 [![Gem Version](https://img.shields.io/gem/v/jekyll.svg)](https://rubygems.org/gems/jekyll)
-[![Build Status](https://img.shields.io/travis/jekyll/jekyll/master.svg)](https://travis-ci.org/jekyll/jekyll)
+[![Linux Build Status](https://img.shields.io/travis/jekyll/jekyll/master.svg?label=Linux%20build)](https://travis-ci.org/jekyll/jekyll)
+[![Windows Build status](https://img.shields.io/appveyor/ci/jekyll/jekyll/master.svg?label=Windows%20build)](https://ci.appveyor.com/project/jekyll/jekyll/branch/master)
 [![Code Climate](https://img.shields.io/codeclimate/github/jekyll/jekyll.svg)](https://codeclimate.com/github/jekyll/jekyll)
 [![Dependency Status](https://img.shields.io/gemnasium/jekyll/jekyll.svg)](https://gemnasium.com/jekyll/jekyll)
 [![Security](https://hakiri.io/github/jekyll/jekyll/master.svg)](https://hakiri.io/github/jekyll/jekyll/master)

appveyor.yml

@@ -0,0 +1,38 @@
+version: "{build}"
+
+clone_depth: 10
+
+build: off
+
+install:
+  - SET PATH=C:\Ruby%ruby_folder_version%\bin;%PATH%
+
+#  - ps: Get-DnsClient | Where-Object {$_.InterfaceAlias -like '*ethernet*'} | Set-DnsClientServerAddress -ServerAddresses ("8.8.8.8","8.8.4.4") -PassThru | Get-DnsClientServerAddress
+#  - gem update --system 2.3.0 --quiet --no-ri --no-rdoc
+
+  - bundle install --retry 5
+
+test_script:
+  - ruby --version
+  - gem --version
+  - bundler --version
+  - bash ./script/cibuild
+
+environment:
+  matrix:
+    - ruby_folder_version: "200"
+      ruby_gems_folder: "2.0.0"
+    - ruby_folder_version: "21"
+      ruby_gems_folder: "2.1.0"
+    - ruby_folder_version: "22"
+      ruby_gems_folder: "2.2.0"
+    - ruby_folder_version: "22-x64"
+      ruby_gems_folder: "2.2.0"
+
+matrix:
+  fast_finish: true
+
+cache:
+  - '%USERPROFILE%\.gem -> Gemfile,jekyll.gemspec'
+  - C:\Ruby%ruby_folder_version%\bin -> Gemfile,jekyll.gemspec
+  - C:\Ruby%ruby_folder_version%\lib\ruby\gems\%ruby_gems_folder% -> Gemfile,jekyll.gemspec