UI Tweaks

[lidavidm]

• Conform to 16dp padding in dining hall list (http://www.google.com/design/spec/layout/metrics-keylines.html#metrics-keylines-keylines-spacing)
• Make font size slightly smaller: 20sp/16sp, based on Google's typographic scale (http://www.google.com/design/spec/style/typography.html#typography-styles)
• Refresh spinner now uses primary color
• 'Closed' text is now a gray

Don't know if you like all these changes, I can revert ones if you want (or just reject the PR :P)

Haven't played with the new SDK/M Preview yet (apparently it's not too stable, just like the last one). (Also, hotel internet is terrible (but at least it's there).)

[ghost]

I :heart: everything in this PR thanks David :D Re: new SDK/M preview. Yeah I'm not even gonna try just because I still have KitKat and thus I'm just sour >.>