Improve placement of Colorized Druplicon on admin/build/themes

2 minor issues on the admin/build/themes form:

1. The colorized druplicon is right next to the theme name. There's no space between the name and the edge of the image.
2. If you’ve form altered the form to reduce the clutter (i.e. you've removed some themes from the list.), color module will still add the druplicon icon for a theme that is no longer in the form.