(Please use meaningful bug summaries - thanks!)

- using a cubic sampler is probably not a good idea, your a going to blur the image, I think you can use gegl_buffer_get directly, and fetch a line

- you can add yourself in the copyright

- you can register an enum for horizontal/vertical, like in the ripple of for gegl_ripple_wave_type

Thanks =)

Corrected version now in the soc-2012-ops branch:

From 635bae8d2f4dd2e1845eac6bafbd78e64143fec9 Mon Sep 17 00:00:00 2001
From: Hans Lo <hansshulo@gmail.com>
Date: Tue, 22 May 2012 18:17:48 +0000
Subject: Shift operation

Shifts each row or column of pixels by a random amount.