Revert "Fix test for Python 3."

This reverts commit 43dd224d52eb4711c68101b40b910d252dacc290.
Revert "Skip reserved byte"

This reverts commit ff3342aeedb9d21897b0b7275dd68d781f149995.
Revert skipping reserved byte.
Merge pull request #51 from msgpack/revert-skip-reserved

Revert skipping reserved bytes.