version 1.17.4 (latest) has incorrect documentation regarding cropping of images #135

• processors.py:337-ish as of commit 6ab9496 says that, for the ImageProcessor class "The crop argument is 4-tuple of (left, top, right, bottom)" this matches with what the pillow library documentation wants (the lib that actually does the cropping).
• The README demonstrates that this should be a dict of the form {left='10%',top='10%',width='80%', height='80%'}.
• no code seems to exist to convert between these forms or even validate the inputs of this dict

whats the intended functionality? which piece of documentation is incorrect since they're both in conflict?