inttypes: use portable types in public headers

loff_t -> int64_t
  __u8 -> uint8_t

Signed-off-by: Noah Watkins <noahwatkins@gmail.com>
rados: include struct timeval definition

Signed-off-by: Noah Watkins <noahwatkins@gmail.com>
Merge pull request #1013 from ceph/port/public-hdrs

use portable types in public headers

Reviewed-by: Sage Weil <sage@inktank.com>