Support generic entity properties

[alexanderkirtzel]

Is your feature request related to a problem? Please describe.
Today I need to know the entity's name, to define an attribute, like data-elb="product" data-elb-product="k:v". It can be difficult to define the entity type if I don't know it.

Describe the solution you'd like
Enhance the syntax with an asterisk to attach properties to every entity it's a child of.

<div data-elb="mother" data-elb-*="type:human" data-elb-mother="label:caring" data-elbaction="load:view">
  <div data-elb="son" data-elb-son="age:23"></div>
  <div data-elb="daughter" data-elb-daughter="age:32">
    <div data-elb="baby" data-elb-baby="status:infant"></div>
  </div>
</div>

The data-elb-*="type:human" attribute should add data: "human" to all, mother, son, daughter, baby entities.

Describe alternatives you've considered
Keep setting data-elb-mother="type:human", data-elb-son="type:human", data-elb-daughter="type:human", data-elb-baby="type:human" instead of just one attribute ...