Merge pull request #35 from Financial-Times/fixes

Linear gradient fix, icon fixes, updated o-hierarchical nav and linting
Use new asset resolve syntax
Merge pull request #41 from Financial-Times/assetsupdate

Use new asset resolve syntax
Merge pull request #49 from Financial-Times/fixes

Fixed background colour and updated main.mustache
Merge pull request #52 from Financial-Times/fixes

Fixed megadropdown demo on mobile, hid abbr logo text, more menu with fe...