UV: Use relative instead of absolute URLs

Fixes #38.

hyrax/config/initializers/hyrax.rb

@@ -131,21 +131,10 @@ Hyrax.config do |config|
   #
   # Default is false
   config.iiif_image_server = true
-  if ENV.fetch('IIIF_TO_SERVE_SSL_URLS', 'false') == 'true'
-    protocol = 'https'
-  else
-    protocol = 'http'
-  end
-
-  if Rails.env.development?
-    port = ENV.fetch('PORT', 3000)
-  else
-    port = nil
-  end
 
   # Returns a URL that resolves to an image provided by a IIIF image server
   config.iiif_image_url_builder = lambda do |file_id, base_url, size, format|
-    Riiif::Engine.routes.url_helpers.image_url(file_id, host: base_url, size: size, protocol: protocol, port: port)
+    Riiif::Engine.routes.url_helpers.image_url(file_id, size: size, only_path: true)
   end
   # config.iiif_image_url_builder = lambda do |file_id, base_url, size, format|
   #   "#{base_url}/downloads/#{file_id.split('/').first}"
@@ -153,7 +142,8 @@ Hyrax.config do |config|
 
   # Returns a URL that resolves to an info.json file provided by a IIIF image server
   config.iiif_info_url_builder = lambda do |file_id, base_url|
-    uri = Riiif::Engine.routes.url_helpers.info_url(file_id, host: base_url, protocol: protocol, port: port)
+    uri = Riiif::Engine.routes.url_helpers.info_url(file_id, only_path: true)
+    uri.sub(/\Ahttp:/, 'https:')
     uri.sub(%r{/info\.json\Z}, '')
   end