Acquiring mutexes is now wraped in a easy to use MUTEX_SECTION macro.
This scheme will be extended for chained lock propagation soon.
Notes:
* NoBug resourcemanagement is now part of the lower layer,
RESOURCE_ENTER/RESOUCE_LEAVE are maintained automatically
* one must still call RESOURCE_ANNOUNCE/RESOURCE_FORGET, because we want
to maintain high level information about resources.
* MUTEX_SECTIONS must not be left with any kind of jump
LUMIERA_MUTEX_SECTION takes now a nobug flag as first argument and
a nobug resource-handle as second argument.
This change works forward for the NoBug resource tracker and
deadlock detector.
