Bug with setp and clim

Hi, unles I'm doing something stupid, setp is buggy.

    > I'm creating a bunch of images using imshow and I want the
    > colormap to be consistent among images. So once they're all
    > drawn, I want to uniformize the color scale. But

    >>>> setp(ax.images, clim= [0,1])

    > does not work because it sets vmin to [0,1] and doesn't
    > affect vmax.

    > On the other hand,
    >>>> ax.images[0].set_clim([0,1])

The latter should not work. The set_clim function in
cm.ScalarMappable has the signature

    def set_clim(self, vmin=None, vmax=None):

Ie, it does not accept the sequence argument, though


should work.

The setp behavior is more of a bug with set_clim than it is with setp.
For properties to work with setp, we need to have all setters work
with a single argument, and so in this we would want to support a
single non-keyword argument which is a length two sequence mean
"[vmin, vmax]"

I just committed changes to support this so if you have svn access
give it a test drive.