Option for not update database

[tomredhot]

Above all, great work!
I have a question / request.
Is it possible to have an option for not to save a field in database?
I explain :
I want to get all the power of your system (replace/delete/helpers etc...), but without create a new field in database for each iteration of an initial image.

(with this "image300" is a thumbnail of "image" )
This work perfectly ONLY if field "image300" exist in database.

To be clear, i dream of an option for $imageFields like "auto_update_database"=> false .
Do you think is possible?

Then maybe I missed something
Thanks!

[tomredhot]

I made a PR ( #50 ) if you want.

[pacoorozco]

Hi @saqueib

Maybe this issue was fixed when you merged the PR #50.