Add test for the multi buildpack, courtesy of https://github.com/AlJohri

tests/apps/multi/bower.json

@@ -0,0 +1,20 @@
+{
+  "name": "test-buildpack-multi",
+  "version": "0.0.0",
+  "authors": [
+    "Al Johri <al.johri@gmail.com>"
+  ],
+  "license": "MIT",
+  "private": true,
+  "directory": "static/components",
+  "ignore": [
+    "**/.*",
+    "node_modules",
+    "statc/components",
+    "test",
+    "tests"
+  ],
+  "dependencies": {
+    "bootstrap-sass": "twbs/bootstrap-sass#~3.1.1"
+  }
+}