Roll Observatory packages and add a roll script

packages/barback/example/aggregate_transformer/lib/recipes-grammas/banana-pudding-recipe.html

Index: packages/barback/example/aggregate_transformer/lib/recipes-grammas/banana-pudding-recipe.html
diff --git a/packages/barback/example/aggregate_transformer/lib/recipes-grammas/banana-pudding-recipe.html b/packages/barback/example/aggregate_transformer/lib/recipes-grammas/banana-pudding-recipe.html
new file mode 100644
index 0000000000000000000000000000000000000000..f3e3b63986b3b48bbb592bbdfdd475b55b186f30
--- /dev/null
+++ b/packages/barback/example/aggregate_transformer/lib/recipes-grammas/banana-pudding-recipe.html
@@ -0,0 +1,28 @@
+
+<h2><a name="banana-pudding">Banana Pudding</a></h2>
+<ul>
+<li>1/4 cup water</li>
+<li>2 Tblsp flour</li>
+<li>1 cup sugar</li>
+<li>6 lg eggs</li>
+<li>1 can evaporated milk</li>
+<li>1 Tblsp vanilla extract</li>
+<li>16 oz sour cream</li>
+<li>3 large bananas, sliced</li>
+<li>1 (16 oz) package of vanilla wafers</li>
+</ul>
+<p>
+Add water to saucepan. Whisk in flour until smooth. Add sugar
+and mix well. Add eggs, one at a time, mixing well after each one.
+Slowly stir in milk, mixing well.</p>
+<p>
+Place pan on low heat. Cook, stirring constantly, until mixture
+is thickened to the consistency of a thick gravy, approximately
+20 minutes. The mixture will start to steam and produce bubbles,
+but you don't want a full boil.</p>
+<p>
+Remove from heat and stir in vanilla. Cool thoroughly. Fold in
+sour cream and mix well.</p>
+<p>
+Layer wafers, bananas, and pudding in a glass serving bowl, such
+as a trifle bowl. Thoroughly chill. Serve with whipped cream.</p>