[style] new .hero style, also:
- padding fixes for dubbel layout
- page-header-title include
- layout options 'hero' and 'no-title'
- About page tests this with the singel layout
[fix] page-header-title include Liquid logic fix
[style] [structure] completely reworked dubbel layout
[fix] [style] proportion changes for dubbel layout and others:
- .narrow figure styles for dubbel
- wide figure styles for dubbel
- big screen scaling for dubbel
- better .site-footer sizing to match different layouts
- ancillary headings
[style] new calculations for .singel .ancillary width and margins
[edit] About implements new styles
Merge pull request #31 from opattison/2014-11-20-dubbel

Dubbel layout enhancements – resolves #32