Update serialization version to v1.16.
Fix errors introduced in previous commit.
Moved debug_print declaration above datum_t so that its friend declaration works in clang.
Merge branch 'v1.15.x' into next
Merge branch 'next' into sam_3185_common
Merge branch 'tim/update-version' into next
Merge branch 'sam_3185_common' into next
Merge branch 'next' of github.com:rethinkdb/rethinkdb into next
Merge branch 'next' into sam_3815_alt