Feature/adding usage info urls

Added "help page" to SDR load. Related rspec tests. Cucumber test as well. See line comments for question re: cucumber test...
@chrpr As you suggest I like the idea of having this as

`expect(document_field_value(field)).to have_link(link)`

where `document_field_value` is something like

    def document_field_value(field)
      document_container.find(:xpath, , "//dt[text()='#{field}']/following-sibling::dd")
    end