You could define a spider attribute that references a callback method
but if this method has a different name than your spider attribute,
the request serializer is not able to find it on the spider class.
With this commit we're fixing this behavior as we're searching for
callback references in the spider object itself instead of looking
for attributes with the same function's name, that could be different.
* add flags to request
* fxi test - add flags to request
* fix test(2) - add flags to request
* fix test(2) - add flags to request
* Updated test to reqser with flags field of request
* Updated documntation with flags field of request
* fix test identation
* fix test failed
* make the change backward comptaible
* remove unrequired spaces, fix documentation request flags
* remove unrequired space
* fx assert equal
* flags default is empty list
* Add flags to request
* add flags to request
* fxi test - add flags to request
* fix test(2) - add flags to request
* fix test(2) - add flags to request
* Updated test to reqser with flags field of request
* Updated documntation with flags field of request
* fix test identation
* fix test failed
* make the change backward comptaible
* remove unrequired spaces, fix documentation request flags
* remove unrequired space
* fx assert equal
* flags default is empty list
* add flags to request squashed commits