OP-1365 Flight code instrumentation API: Changed API to use handlers (opaque pointers) to counter struct instead of an index, fix Search function, create does check if coutner exists and return existing handler
OP-1365 Flight code instrumentation API: Add some helper macros to simplify the addition of instrumentation code to a module.
Note: Look at next commit for an example use case.
OP-1365 Flight code instrumentation API: Sample use of instrumentation in Atittude module.
When instrumentation is enabled at board level (pios_board.h, enable PIOS_INCLUDE_INSTRUMENTATION) PIOS_INSTRUMENT_MODULE setups the module to be instrumented.