There has been a continuous problem that the counter:CheckStatus function

called from the status task messed up count processing. This has now been
resolved in this way:
- A new function ReadStatus and  a lastStatus filed have been added
  to the countable interface.
- CountTaskFunc updates the lastStatus field.
- ReadStatus just returns that field.
- ReadStatus is now being called by the status task.

interface.h

@@ -62,11 +62,13 @@
    typedef struct {
                    int ID;
                    int running;
+                   int lastStatus;
                    int (*Halt)(void *self);
                    void (*SetCountParameters)(void *self, float fPreset,
                                              CounterMode eMode);
                    int (*StartCount)(void *self, SConnection *pCon);
                    int (*CheckCountStatus)(void *self, SConnection *pCon);
+                   int (*ReadStatus)(void *self, SConnection *pCon);
                    int (*Pause)(void *self, SConnection *pCon);
                    int (*Continue)(void *self, SConnection *pCon);
                    int (*TransferData)(void *self, SConnection *pCon);