1.change some preference setting.
2.add new post of this week.
	modified:   _config.yml
	modified:   _posts/2014-07-05-welcome-to-jekyll.markdown
	new file:   _posts/2014-7-12-Weekly-Report-week-26.markdown
	modified:   about.md
3.detail what I have learn
Merge branch 'master' of https://github.com/Leorowe/leorowe.github.io

Conflicts:
	_posts/2014-7-12-Weekly-Report-week-26.markdown