allow json files in _data dir
add tests for json data
document json support
dot json;
Merge pull request #2369 from jekyll/json-data
Update history to reflect merge of #2369 [ci skip]
Update CI to use Ruby 2.1.2
Merge pull request #2374 from albertogg/update-ruby
Update history to reflect merge of #2374 [ci skip]
Update anchor_links.html.

* fix `TypeError` when we are in home
* remove default type and encoding
* format the code
Include anchor_links before the end closing `body` tag.
Fix wrong post reference.