Restore_colors params fixed in Insight

Tiny fix to parameters in Restore_colors as requested here: https://www.openmicroscopy.org/community/viewtopic.php?f=4&t=7431&start=10#p13738

Screen-shots show the script UI in Insight before and after this fix:

![screen shot 2014-03-24 at 12 03 09](https://f.cloud.github.com/assets/900055/2498972/916c7f14-b34e-11e3-8af7-23cb3fffe187.png)

![screen shot 2014-03-24 at 12 06 53](https://f.cloud.github.com/assets/900055/2498973/95b859ee-b34e-11e3-853a-6915f7d26c0d.png)

Seems Insight is a bit sensitive to parameter grouping - something to watch out for!