* apply R8157 from the dav-rework branch:

* apply R8157 from the dav-rework branch:
* make the template loader recursive; now t/ can contain subdirectories
* create the template key from the directory relative to t/ with '/' seperated by _ :
* t/knrooms/rooms.html is represented as knrooms_rooms so it would be equal to t/knrooms_rooms.html
* have an optional dbg/ directory next to t; this will be used for creating special templates for debugging / testing