Minor javadoc comments for CompletionHandler

[Alan Bateman]

Ben Horowitz wrote:
> Hi,
>
> In the javadoc for CompletionHandler:
>
>    "The completed is invoked" should read "The completed method is invoked"
>    "The cancelled is invoked" should read "The cancelled method is invoked"
>
> (Re-sending from my subscribed address this time; apologies for duplicates.)
>
> Regards,
> Ben
>   
Thanks! There are probably a few other typos lurking so if see others 
(or come across wording that isn't clear, etc.) then please let us know.

-Alan.