Hook up writes to 1.0 API

[richmolj]

There is still refactoring of internals to do, particularly around the proxies/runner, but this adds 1.0 support for writes:

def create
  employee = EmployeeResource.build(params)

  if employee.save
    render jsonapi: employee
  else
    render jsonapi_errors: employee
  end
end

def update
  employee = EmployeeResource.find(params)

  if employee.update_attributes
    render jsonapi: employee
  else
    render jsonapi_errors: employee
  end
end

def destroy
  employee = EmployeeResource.find(params)

  if employee.destroy
    render jsonapi: employee
  else
    render jsonapi_errors: employee
  end
end

This will honor the attribute types, see spec/persistence_spec.rb for detailed usage.

Questions:

• save and update_attributes functionally do the same thing, and the alias is just to match rails convention. Is there anything better we can do here?

Other notes:

• All tests now pass
• This commit wires-up write functionality, it does not refactor the existing write functionality. This can come later.
• sort and filter customizations now optionally accept a type. If given a type, we will create a sort-only or filter-only attribute under-the-hood. We will still raise errors if not given a type, or if the attribute was specifically marked unsortable/unfilterable.
• Adds jsonapi_errorable as a dependency, which sets us up to remove the top-level jsonapi_suite gem altogether.
• Moves render_jsonapi completely from Base - this is now proxy.to_jsonapi. It will still respect def default_render_jsonapi_options;end if defined in the controller.
• Adds Resource#typecast convenience method.

[richmolj]

@wadetandy