New timer implementation

This is first part of new softserial code. Main timer code is changed, changes to rest of code are kept to minimum.

macros for BASEPRI based synchronization are added to project (atomic.h)

TIMER_PERIOD fixed in pwm_rx.c

src/main/drivers/pwm_output.c

@@ -34,13 +34,7 @@
 typedef void (*pwmWriteFuncPtr)(uint8_t index, uint16_t value);  // function pointer used to write motors
 
 typedef struct {
-#ifdef STM32F303xC
-    volatile uint32_t *ccr;
-#endif
-
-#ifdef STM32F10X
-    volatile uint16_t *ccr;
-#endif
+    volatile timCCR_t *ccr;
     uint16_t period;
     pwmWriteFuncPtr pwmWritePtr;
 } pwmOutputPort_t;