Fixes #13849 - Now the facets will not require id attribute for update

fixes #13567 - fixing locale:pack

apparently, the PO generator treats underscore as something important,
it assumes it's the GetText underscore method, thus, breaking
things in a spactacular way.
removing it solves it.

Fixes #13216 - Added ability to extend API by creating facet subnode
This commit adds the ability for plugins to extend Host model with custom data that will be stored in a facet model.
In order to show this data an extension point is added to Host's view API, so the properties list can be extended by the facet....