Member profile

Improved design/layout of member profile page and added an OSM/mapbox map.  It's not perfect but I think it's a considerable improvement.

A point of interest: I created content areas "subtitle" and "buttonbar" which you can use like this:

    - content_for :title, "A page"
    - content_for :subtitle, "With a subtitle"
    - content_for :buttonbar do
      = link_to "Do this", link, :class => 'btn btn-default'
      = link_to "Do that", link, :class => 'btn btn-default'

The idea of this is to standardise the layout of the top section of the page.  I also moved the crop detail page over to using this system, hence a bunch of crop stuff in this PR.
This breaks two tests in spec/controllers/member_controller_spec.rb which tested that we *didn't* return JSON for members. They were added in 1ccaab30, which makes it pretty clear that it was a deliberate policy decision: was that for privacy reasons? If so, are we changing that decision now?