Fix struct alignment.
Fix struct alignment.

    We over padded. This was bad for 2 reasons:
        - We wasted memory.
            For structs containing just bytes, we
            almost doubled the memory usage.

        - We were not C compatible.
            Normally I wouldn't care, but for the syscall
            ABIs, our data needs to work.

8l/myrddin,8l/myrddin,oridb/mc,oridb/mc,oridb/mc,oridb/mc