Documentation for disabling a web item in a plugin is incorrect (including documentation about the same feature for several other plugin module types)

Our documentation shows that in order to disable a web item, you should use the attribute like this:

<web-item ... disabled="true">

From a support case we found that this isn't correct and the proper way to disable a web item is:

<web-item ... state="disabled">

If the latter is intended to be the correct way to disable a web item, we should update the docs to reflect this.