message: Remove extra on.
diff: @@ -35,7 +35,7 @@ The notifier is built using
  and therefore can be imported with AMD, CommonJS2 or as property in root.
  If you prefer not to host the library yourself,
  -airbrake-js is available on the excellent on
  +airbrake-js is available on the excellent
  [cdnjs](https://cdnjs.com/libraries/airbrake-js).
  ## Basic Usage
  