Fix heapsort, add test

include/ucore/heapsort.h

@@ -8,11 +8,20 @@ extern "C" {
 #endif
 ///compare function. Needs only to return < 0 if 
 //the first element is less than the second
-typedef int (*uc_hs_cmp)(const void *, const void *);
+typedef int (*uc_hs_cmp)(const void *, const void *, void *cookie);
+//swap function
+typedef void (*uc_hs_swp)(void *, void *);
 
-void
-uc_heapsort(void *base, size_t count, size_t width,
-     uc_hs_cmp cmp);
+/** Sort an array.
+ * @param base start of array
+ * @param count number of elements in array
+ * @param width size of each element
+ * @param cmp compare function
+ * @param swap swap function
+ * @param cookie user pointer passed back to compare function
+ */
+void uc_heapsort(void *base, size_t count, size_t width,
+                 uc_hs_cmp cmp, uc_hs_swp swap, void *cookie);
 
 #ifdef __cplusplus
 }