Move the tables and columns to migrate into a single place

gems/houdini_upgrade/lib/houdini_upgrade.rb

@@ -4,5 +4,29 @@
 require "houdini_upgrade/engine"
 
 module HoudiniUpgrade
-  # Your code goes here...
+  require 'houdini_upgrade/table_to_migrate'
+  UPLOADERS_TO_MIGRATE = [
+    TableToMigrate.new(:nonprofits, [:main_image, 
+      :second_image, 
+      :third_image, 
+      :background_image, 
+      :logo]),
+    TableToMigrate.new(:campaigns, [
+      :main_image, 
+      :second_image, 
+      :third_image, 
+      :background_image, 
+      :logo
+    ]),
+    TableToMigrate.new(:events, [
+      :main_image,
+      :background_image
+    ]),
+    TableToMigrate.new(:image_attachments, [
+      :file
+    ]),
+    TableToMigrate.new(:profiles, [
+      :picture
+    ])
+  ]
 end