fixed ls -h and added test

lib/pry/default_commands/ls.rb

@@ -143,7 +143,7 @@ class Pry
           opt.on :h, "help", "Show help"
         end
 
-        next output.puts(opts) if opts.present?(:help)
+        next output.puts(opts.to_s) if opts.present?(:help)
 
         obj = args.empty? ? target_self : target.eval(args.join(" "))
 

test/test_default_commands/test_ls.rb

@@ -22,7 +22,13 @@ describe "ls" do
     end
   end
 
-  describe "methods" do 
+  describe "help" do
+    it 'should show help with -h' do
+      mock_pry("ls -h").should =~ /Usage: ls/
+    end
+  end
+
+  describe "methods" do
     it "should show public methods by default" do
       mock_pry("ls Class.new{ def goo; end }.new").should =~ /goo/
     end