FIX: images:compress rake task

Optimized a few unoptimized PNGs.

lib/tasks/images.rake

@@ -2,11 +2,12 @@ require_dependency "file_helper"
 
 task "images:compress" => :environment do
   images = Dir.glob("#{Rails.root}/app/**/*.png")
-  image_sizes = Hash[*images.map { |i| [i, File.size(i)] }.to_a.flatten]
-  FileHelper.optimize_images!(images) do |name, optimized|
-    if optimized
-      new_size = File.size(name)
-      puts "#{name} => from: #{image_sizes[name.to_s]} to: #{new_size}"
+  image_sizes = images.map { |i| [i, File.size(i)] }.to_h
+
+  images.each do |path|
+    if FileHelper.optimize_image!(path)
+      new_size = File.size(path)
+      puts "#{path} => from: #{image_sizes[path]} to: #{new_size}"
     end
   end
 end