getDelayed seems to return a Boolean not a "string (Binary object)" as the docs state

I'm not sure if this is a doc error or a code error, but the documentation for getDelayed [1] states it returns a "string (Binary object)" when in fact it returns a Boolean.

The return of a Boolean is likely the intended response as getDelayed implies the use of a callback.

I've marked this issue as being related to both docs & library, though, in case I've missed something.

[1] http://www.couchbase.com/docs/couchbase-sdk-php-1.0/api-reference-retrieve.html#table-couchbase-sdk_php_get-delayed