Simple helper file for standard text sizes in material design. The sizes are provided by the material design documentation https://www.google.com/design/spec/style/typography.html#typography-roboto
Too many type sizes and styles at once can wreck any layout. A typographic scale is a limited set of type sizes that work well together, along with the layout grid. The basic set of styles are based on a typographic scale of 12, 14, 16, 20, and 34.