release and debug mode heap allocation

[Aleix Conchillo Flaqué]

More information:

number of tasks: 30
number rate monotonic periods: 11
number of semaphores: 29
number of mqueues: 26

My configuration:

#define CONFIGURE_MAXIMUM_TASKS 48
#define CONFIGURE_MAXIMUM_PERIODS 32
#define CONFIGURE_MAXIMUM_SEMAPHORES 32
#define CONFIGURE_MAXIMUM_MESSAGE_QUEUES 32