Make layout and typography more flexible

• Fix fonts as in #189 (closed)
• Base fonts and layout on flexible ems
• Decide on max-widths for site and app layouts
• Tidy up recent Spotlight homepage using new layout
• Fix h1 with icon/h1 strong title/Support h1 styling when body classes from https://source.ind.ie/better/builder/issues/117 is complete
• Style site trackers list popover
• Style trackers collection list (/trackers/alexa-top-500-news/) consistently with above popover
• Sort out necessary padding above footer
• Make review quotes work for single and multiple paragraph reviews (probably needs <span>s back again)
• Even spacing around Statistics/app home page

Showstoppers

• Make home phones header match size of current homes header
• Pull in newer content from master
• Fix gaps on top of headings on app (needs https://source.ind.ie/better/builder/issues/119)
• Look at tightening header line heights (may need to adjust all other measurements on headings accordingly)
• Make paragraph bottom margins larger than the space between paragraph lines
• Fix space above protect yourself on homepage