README.md in usda_fdc-0.1.1 vs README.md in usda_fdc-0.2.0

- old
+ new

@@ -1,7 +1,9 @@
 # UsdaFdc
 
+[![Gem Version](https://badge.fury.io/rb/usda_fdc.svg)](https://badge.fury.io/rb/usda_fdc)
+
 A Ruby interface to the USDA [FoodData Central](https://fdc.nal.usda.gov) API.
 
 ## Installation
 
 To install the latest release:
@@ -23,9 +25,17 @@
 ```ruby
 client = UsdaFdc::Client.new('your_api_key')
 client.food(534358)
 
 #=> { "dataType" => "Branded", "description" => "NUT 'N BERRY MIX", "fdcId" => 534358, ... }
+```
+
+You can also configure the default API key globally for all `UsdaFdc::Client` instances:
+
+```ruby
+UsdaFdc.configure do |config|
+  config.api_key = 'your_api_key'
+end
 ```
 
 For more information on interacting with the API, including accepted parameters and response formats, check out the official USDA FDC [API guide](https://fdc.nal.usda.gov/api-guide.html).
 
 ## Development