Resize images on a per-service basis

[mhucka]

Currently, when an input image is larger than one of the destination services, Handprint resizes the input image to the max size accepted by any of the destination services. This means that some services might accept a larger image, and might produce different results than when given the (smaller) resized image.

Instead of resizing once, Handprint could treat each service separately and resize only for those that need a smaller image.