Add browsersync refresh to gulp pipes for templates.
Meaningful updates to the base form view and base entity model.

* Split model related entities map into related entities and related
collections, so that the links can be treated as such.
* Sync form changes to the underlying model immediately instead of
serializing the form into the model on submit. This should make the
submit faster, and is simpler.
* Prevent related entities (that are not part of a model attributes)
from being sent to the server as part of a POST or PUT.