Existing styles now prefixed with ‘article-‘.
Added general styles.
Updated demo page to use o-grid and to show both general and article styles according to consistent categorisation.
Naming of heading styles TBC.
General and article styles via a wrapper class
Corrected text in demo page.
Reorganised styles in order to incorporate styles from Velcro.
Now uses new uses cases added in o-colors 2.1.0
Merge pull request #1 from Financial-Times/general-and-article

Now includes general typographic styles as well as article-specific ones.