pass the app to getModel when constructing a model from the options passed to a view

Models generally expect to have access to the app object, but if they're constructed from the options passed to a view they're currently missing the app. This is a quick fix for that by passing options.app (which is required) to the modelUtils.getModel function.
Currently `parseOptions` which calls `parseModelAndCollection` will raise if `options.app` is not present. Do you think it's still worth checking here also?