Don't set the field to have nested empty hashes unless explicitly told to do so.

[NullVoxPopuli]

Desired behavior:

metadata = Metadata.new
metadata.data.should be_nil
metadata.data.nested_data.should be_nil
metadata.should == {}
metadata.data = {}
metadata.should == {data: {}}

Current Behavior:

metadata = Metadata.new
metadata.data == {}
metadata.data.nested_data == {}
metadata == {data: {nested_data: {}}

this is a problem if one of the nested keys we call is eventually supposed to be a non Hash

example:

metadata = Metadata.new
id = metadata.property.id
klass.find(id)

=> errors cause id is a hash, rather than an id or nil