Merge remote-tracking branch 'origin/master'

Conflicts:
	.gitignore
	_config.yml
	_layouts/default.html
	_layouts/post.html
	_plugins/pandoc_markdown.rb
	assets/images/f7b69fd77642212f8ad6f52b86bb0991103cf559.svg
	assets/js/mathjax-config.js
	favicon.ico
	index.html
	tikz.py