Docs: keep inherited stuff within the component

[vkrv]

Add to documentation to particular component information about it's inheritance tree (e.g. WebItem->Rectangle->Item), so inherited properties and methods can be easily accessible.
Having kind of inheritance structure would be nice:
"interits": {
"name": "Rectangle",
"ref": "core/Ractangle",
"inherits": {
"name": "Item",
"ref": "core/Item",
"inherits": {
"name": "Object",
"ref": null,
"inherits": null
}
}
}