Revert "Move 9-patch deletion outside of `resize-image`."

This reverts commit aa6a3044f25d8fbe64d24a6fbd5f1cb7fd972e41.
Adds the main UI using Seesaw (not operational yet).
Adds drag & drop and saves the images on the same directory of the dragged folder.
Shows a dialog when the image resizing ends.
Adds the checkbox for drawable-ldpi.
Adds :gen-class to allow the uberjar creation.
Decreases the size of the window to work on 1024x768 resolutions.