Allow page building of landing pages

[chrisdmacrae]

Struggle:

See #14

Solution

A medium-style editing experience is:

• A hero area
  • Configurable image
  • Title
  • Subtitle
  • Tags
• A block style layout, in one column
• A fixed title/sharing area
• A footer area
  • Author info
  • Tags
  • Responses
  • Social sharing
  • Other articles

The ability to:

• Draft with these blocks on a page
• Highlight any text and:
  • Make a highlight (for others to see) via Github and Tina, or;
  • Make a comment (for others to see) via webmentions and Tina - stretch goal

The following blocks:

• Everything from Add page building for articles #15 , plus;
• Flex two, configurable to be:
  • any background
  • fluid or constrained width
  • vertical or horizontal
• Flex col, configurable to be:
  • breakpoint specific colspans
• CTAs
  • button
  • link
• cover block (responsive, 100% height)
• hero block
  • basically copy all bootstrap hero sizes
• jumbotron with block internals
• cards with block intervals
  • card heading
  • card body
  • card footer
• reference
  • article/page
  • project
  • event
• reference list
  • article/page
  • project
  • event