Train 0.18.0

0.18.0 (2016-08-26)

Full Changelog

Merged pull requests:

• Allow JSON 2.0 on Ruby 2.2 and above #144 (jkeiser)
• Enable Ruby 2.3 in Travis, make it default suite #143 (jkeiser)
• Add the darwin platform family #141 (tas50)
• update integration test dependencies #139 (tas50)
• Add badges to the readme #138 (tas50)
• use --decode on base64 command to maintain compatibility with Darwin. #137 (thomascate)