This code was assuming it could copy double's in/out of char *'s with just
casts and normal copies. This blows up on anything which enforces alignments.
Change the generic case for the ATOM to just have a special double field.
For the serialization routines memcpy the double in and provide a union to
memcpy it out to that also contains a single double value. This ensures
alignment is correct and it won't SIGBUS anymore.
Bump pkg to nb1
