FORMUS3IC_LAS3 / embb

mtapi_network_c: signaling of task completion is now atomic

(Merge was previously reverted accidentally. Re-applying merge to fix this.)

This reverts commit 554c76f7, reversing
changes made to fc660db0.

Fixed the buggy implementation of the id pool (did give out fewer elements as capacity, with repeated operations capacity was further reduced).

mtapi_c: do not notify all worker threads on task start, but just the one the task was initially assigned to

Ticket EMBB-349

mtapi: added description of default node attributes in mtapi_c and fixed typo in mtapi_cpp documentation