adds text_with_links helper and use that in any comment.body in views, adds test to check for malicious injections in comment body

app/helpers/text_with_links_helper.rb

@@ -0,0 +1,9 @@
+module TextWithLinksHelper
+
+  def text_with_links(text)
+    return unless text
+    sanitized = sanitize text, tags: %w(a), attributes: %w(href)
+    Rinku.auto_link(sanitized, :all, 'target="_blank" rel="nofollow"').html_safe
+  end
+
+end