Bug fix in allocation memory for non-multiple of 8 sizes

[Jgmedina95]

Attempt to fix bug in size allocation for non-multiples of 8.

b->data = calloc((size + 7) / 8, 1);

and then in the bloom_read function
b->data = (char *)malloc((m + 7) / 8);

To avoid issues with older version, I've changed FILE_VERSION to 2u
and then handle different versions with if statements when reading saved bloom filters at the end.
Hard to test whether this change will affect older versions, but this version handling approach
will work as a safeguard without having issues with bloom filters saved before this change.