Allow disable/enable gameobjects with child gameobjects at the same time

To `enable\disable` go you need to send a separate message:

msg.post(url, "enable")
msg.post(url, "disable")

But sometime I need to `enable/disable` go with all the children.

For example the go named **"cell"**:

In this case I need to disable all other gameobjects: **"cell_back"**, **"cell_pos"**, etc

Maybe it would be better to add separate messages like **"disable_all"** or **"disable_with_children"**?

This is how **nodes** work in GUI. You can simply `disable/enable` the parent **node**

Start by tracing the msg.post enable/disable entry points and how gameobject parent-child relationships are handled. Determine the intended API for applying the state to a parent and all children, then verify that enabling or disabling the parent produces the expected state for every child.

Written by the indexing model from the issue text.