Make Midnight default admin color scheme

[alexvorn2]

I think the default style is too dark, the Midnight color scheme looks more better in my opinion. So my idea is to make it default, the the Default rename to Dark or something else.

[iammattthomas]

For reasons of branding and usability I'm going to suggest that we stick with the default color scheme as it's been designed. We've debated the sidebar color throughly during MP6's development; I'm not aware of any objective reasons why it needs to be lightened.

[iammattthomas]

Didn't see nacin had already changed the resolution.