Support for loose lists

[SamyPesse]

Markdown supports two types of list: loose and normal.

Loose list have items separated by new lines, and output paragraphs in lists.

Reference: http://spec.commonmark.org/0.24/#list

Questions

• How should we distinguish these lists?
  • Using different token types?
    • It could a problem in draft
  • By parsing inner content as paragraph (for loose) or unstyled (for normal)