Production ready

• New API
  • ServeDir - ServeDir serves files from a directory
  • DefaultHTTPErrorHandler - Invokes the default HTTP error handler
• Improved router performance
• More test coverage
• Fixed issues
  • #37
  • #71
  • #77
  • #86
  • #91
  • #95
  • #96
  • #100
  • #103
• Examples
  • Steaming response
• New URL for the website http://echo.labstack.com