All interfaces which are available get registered in a tree.
This will be used internal for lookup interfaces. The higher level calls
will be an amalgamation of this lookup and the upcoming plugindb and
loader.
* lumiera_interface are now static structures, never wrritten
* introduced a lumiera_interfacenode which manages the dynamic data
of interfaces. The interfaceregistry now holds this nodes.
All interfaces which are available get registered in a tree.
This will be used internal for lookup interfaces. The higher level calls
will be an amalgamation of this lookup and the upcoming plugindb and
loader.