Revert "bump mongo dependency" -- we weren't ready for this yet!

This reverts commit ea083c3474.

install/package.json

@@ -59,7 +59,7 @@
         "material-design-lite": "^1.3.0",
         "mime": "^2.2.0",
         "mkdirp": "^0.5.1",
-        "mongodb": "3.0.8",
+        "mongodb": "2.2.33",
         "morgan": "^1.9.0",
         "mousetrap": "^1.6.1",
         "mubsub": "^1.4.0",