Reloading HstNode when nodetype has changed fails and can lead to NPE during model loading

It is really a corner case but there is a scenario now where the HstNode cache is not reloaded correct:

reproduction:

1) start archetype project and request /site
2) then remove http://localhost:8080/cms/console/?path=/hst:hst/hst:configurations/myhippoproject/hst:pages/home/main/lists and copy /hst:hst/hst:configurations/myhippoproject/hst:workspace/hst:containers/home/lists to
/hst:hst/hst:configurations/myhippoproject/hst:pages/home/main/lists

Now effectively the node 'lists' has been changed from being a hst:referencecomponent nodetype to hst:containercomponent

Now the hst model reload results in an NPE, because the HstNode for /hst:hst/hst:configurations/myhippoproject/hst:pages/home/main/lists still 'thinks' it is a hst:referencecomponent