Fixed timing of log and added mechanism to setup faces to nodes which…

… are more than a hop away

- Time is now logged in nanoseconds (with microsecond precision), not added to upstream yet
- The node abstraction class has a method to add the prefix of another node and the gateway from which it should be reachable
- Improved CCNLiteProcess so that it is possible to add several prefix to the same physical network face (before that every prefix created a new network face to the same target)