1.0.0

• The first argument of Renderer#send can be a string or a {message:string,type:string} now.
  • The type is default to "rtl" . Other value like "ltr" , "top" , "bottom" can also be used.
• Added Renderer#registerDanmakuType to add user defined danmaku type.
• Export class Danmaku used to create user defined danmaku type.