all flight: use pios_thread
all pios_config.h: changed unit of PIOS_EVENTDISPATCHER_STACK_SIZE to bytes
pios_mutex: add missing "" in #error statement
pios_semaphore: add missing "" in #error statement
GenericI2CSensor/i2c_vm: use pios_thread only if PIOS_INCLUDE_FREERTOS is defined
This is not an optimal solution but the cleanest to get the unit test running again.
Ideally a unit test would use the PiOS simulation and thus have access to all os APIs.
tests/i2c_vm: remove simulated FreeRTOS API functions