SequenceDiagram 时序图/序列图
Based on SequenceDiagram.js：
http://bramp.github.io/js-sequence-diagrams/
#### Setting { sequenceDiagram : true } #### Syntax ```seq ......... ``` # or ```sequence ......... ``` #### Example ```seq A->B: Message B->C: Message C->A: Message ``` ```sequence Andrew->China: Says Hello Note right of China: China thinks\nabout it China-->Andrew: How are you? Andrew->>China: I am good thanks! ```