[joyent|compute] Added #list_datacenters

lib/fog/joyent/compute.rb

@@ -16,7 +16,7 @@ module Fog
       model_path 'fog/joyent/models/compute'
       request_path 'fog/joyent/requests/compute'
 
-      # request :list_datacenters
+      request :list_datacenters
       # request :get_datacenter
 
       # Keys

lib/fog/joyent/requests/compute/list_datacenters.rb

@@ -0,0 +1,17 @@
+module Fog
+  module Compute
+    class Joyent
+
+      class Real
+        def list_datacenters
+          request(
+            :expects => 200,
+            :method => :'GET',
+            :path => '/my/datacenters'
+          )
+        end
+      end # Real
+
+    end
+  end
+end