bin/image_optim in image_optim-0.3.2 vs bin/image_optim in image_optim-0.4.0

@@ -18,9 +18,13 @@
 
   op.on('--[no-]threads NUMBER', Integer, 'Number of threads or disable (defaults to number of processors)') do |threads|
     options[:threads] = threads
   end
 
+  op.on('--[no-]nice NUMBER', Integer, 'Nice levle (defaults to 10)') do |nice|
+    options[:nice] = nice
+  end
+
   ImageOptim::Worker.klasses.each do |klass|
     bin = klass.underscored_name.to_sym
     op.on("--[no-]#{bin} PATH", "#{bin} path or disable") do |path|
       options[bin] = path
     end