Instead of using spoiler boolean and spoiler_text, simply check for non-blank spoiler_text

Federate spoiler_text using warning attribute on <content /> instead of a <category term="spoiler" />
Clean up schema file from accidental development migrations

app/services/process_feed_service.rb

@@ -103,6 +103,7 @@ class ProcessFeedService < BaseService
         url: url(entry),
         account: account,
         text: content(entry),
+        spoiler_text: content_warning(entry),
         created_at: published(entry)
       )
 
@@ -223,6 +224,10 @@ class ProcessFeedService < BaseService
       xml.at_xpath('./xmlns:content', xmlns: TagManager::XMLNS).content
     end
 
+    def content_warning(xml = @xml)
+      xml.at_xpath('./xmlns:content', xmlns: TagManager::XMLNS)['warning']
+    end
+
     def published(xml = @xml)
       xml.at_xpath('./xmlns:published', xmlns: TagManager::XMLNS).content
     end