Update msgpack to 1.4.2. - 1.4.1 was yanked
Update msgpack to 1.4.2.
- 1.4.1 was yanked

rubygems/rubygems.org,rubygems/rubygems.org,sonalkr132/rubygems.org,sonalkr132/rubygems.org,rubygems/rubygems.org,sonalkr132/rubygems.org,rubygems/rubygems.org,sonalkr132/rubygems.org