Fetching a collection sends the collection's data.

[danasilver]

1. Fetch all nodes (middguard.Nodes.fetch();). No data is sent (because the front-end has no nodes at this point).
2. Something else fetches all nodes (middguard.Nodes.fetch();). This will send the toJSON() of the middguard.Nodes collection as data. If we're filtering by data to fetch, we'll send back nothing, instead of all the nodes. This empties the middguard.Nodes collection.

Not sure if this is a bug in Backbone.iosync or our usage. Needs more investigation.