Add post about jekyll-xkcd-embed
Merge pull request #6 from RobbertJongeling/content_staging

Add @RobbertJongeling's post about jekyll-xkcd-embed
added some content about returned html
fixes
Merge pull request #7 from RobbertJongeling/content_staging

Added content about returned html to jekyll-xkcd-embed post
html -> HTML
Add manual excerpt to XKCD post