Recaptcha support added when reporting screenshots

There's lots of spam recently. We need to do something against it.

app/controllers/packages_controller.rb

@@ -177,10 +177,12 @@ class PackagesController < ApplicationController
   # Receive an anonymous report from a user to have a screenshot removed.
   def report_screenshot
     @screenshot = Screenshot.find(params[:id])
-    @screenshot.delete_reason = params[:delete_reason]
-    @screenshot.markedfordelete = true
-    @screenshot.save!
-    flash['notice'] = "Screenshot reported. The moderators will deal with it."
+    if verify_recaptcha
+      @screenshot.delete_reason = params[:delete_reason]
+      @screenshot.markedfordelete = true
+      @screenshot.save!
+      flash['notice'] = "Screenshot reported. The moderators will deal with it."
+    end
     redirect_to :back
   end
 

app/views/packages/_report_dropdown.slim

@@ -9,4 +9,5 @@
     the screenshot should get removed:
   = form_tag(report_screenshot_path(screenshot.id))
     = text_area_tag 'delete_reason', nil, class: 'input-group-field', maxlength: 100, rows: 3, cols: 50
+    = recaptcha_tags
     = submit_tag 'Request removal', class: 'button alert'