modify bit_fmt to use brackets whenever there is more than one bit

   set rather than one _set of_ consecutive bits. For example
   "1-3" is now printed as "[1-3]" and "3" stays the same, and
   "[1-3,5-6]" also stays the same

src/common/bitstring.c

@@ -920,8 +920,10 @@ bit_fmt(char *str, int len, bitstr_t *b)
 		if (bit_test(b, bit)) {
 			count++;
 			start = bit;
-			while (bit+1 < _bitstr_bits(b) && bit_test(b, bit+1))
+			while (bit+1 < _bitstr_bits(b) && bit_test(b, bit+1)) {
 				bit++;
+				count++;
+			}
 			if (bit == start)	/* add single bit position */
 				ret = snprintf(str+strlen(str), 
 				               len-strlen(str),