Everything from markdown plus GFM features:
Underscores_are_allowed_between_words.
GFM adds syntax to strikethrough text, which is missing from standard Markdown.
~~**works with other formatting**~~
for (var i = 0; i < items.length; i++) {
console.log(items[i], i);
- [ ] Incomplete task list item
- [x] **Completed** task list item
* SHA: be6a8cc1c1ecfe9489fb51e4869af15a13fc2cd2
* User@SHA ref: mojombo@be6a8cc1c1ecfe9489fb51e4869af15a13fc2cd2
* User/Project@SHA: mojombo/god@be6a8cc1c1ecfe9489fb51e4869af15a13fc2cd2
* User/Project#Num: mojombo/god#1
See http://github.github.com/github-flavored-markdown/.