README.md in mpower-1.0.5 vs README.md in mpower-1.0.6

@@ -49,14 +49,14 @@
 
 ## Create your Checkout Invoice
 
     co = MPower::Checkout::Invoice.new
 
-Params for addItem function `add_item(name_of_item,quantity,unit_price,total_price)`
+Params for addItem function `add_item(name_of_item,quantity,unit_price,total_price,optional_description)`
 
     co.add_item("13' Apple Retina 500 HDD",1,999.99,999.99)
-    co.add_item("Case Logic laptop Bag",2,100.50,201)
+    co.add_item("Case Logic laptop Bag",2,100.50,201,"My optional item description")
     co.add_item("Mordecai's Bag",2,100.50,400)
 
 ## Set the total amount to be charged ! Important
 
     co.total_amount = 1200.99
@@ -66,12 +66,12 @@
     co.add_tax("VAT (15)",50);
     co.add_tax("NHIL (10)",50);
 
 ## You can add custom data to your invoice which can be called back later
 
-    co.custom_data["Firstname"] = "Alfred"
-    co.custom_data["Lastname"] = "Rowe"
-    co.custom_data["CartId"] = 929292872
+    co.add_custom_data("Firstname","Alfred")
+    co.add_custom_data("Lastname","Rowe")
+    co.add_custom_data("CartId",929292872)
 
 ## Redirecting to your checkout invoice page
 
 		if co.create
 			redirect_to co.invoice_url