Minor fixes to silence warnings and replaced two asprintf uses

src/bloom.c

@@ -61,7 +61,7 @@ static int bloom_check_add(struct bloom * bloom,
   register unsigned int a = murmurhash2(buffer, len, 0x9747b28c);
   register unsigned int b = murmurhash2(buffer, len, a);
   register unsigned int x;
-  register unsigned int i;
+  register int i;	// TODO why was it unsigned?
 
   unsigned bucket_index = (a % bloom->buckets);