[scikits-image] Restore previous io plugins (#152)

[Stéfan van der Walt]

On Sun, Feb 26, 2012 at 12:25 PM, Christoph Gohlke <cjgohlke at gmail.com> wrote:
> Instead of restoring the default plugins after each test module, maybe it
> would be better/cleaner/safer for the tests to never change the default
> plugins but to just load the plugin and explicitly specify the plugin in
> each imread, imwrite, etc. function call? It seems there is currently no way
> to load a plugin without making it the default. This could be achieved by
> changing the use_plugin function to accept another option for the `kind`
> parameter, e.g. an empty string, signaling that the plugin should only be
> loaded. Probably too late for the 0.5 release.

Ideally, the ``imread(..., plugin='fits')`` functionality should
auto-load the FITS-plugin---I should see why this is not currently
working, because it seems like a bug.

Stéfan