Travis Elixir build

.travis.yml

# for releases available at s3.hex.pm/builds/elixir
# using language: elixir is simpler

language: erlang
otp_release:
  - 18.1
before_install:
  - curl -sSL https://raw.githubusercontent.com/taylor/kiex/master/install | bash -s
before_script:
  - kiex install $ELIXIR_VERSION
  - kiex use $ELIXIR_VERSION
  - mix local.hex --force
  - MIX_ENV=test mix deps.get
script: MIX_ENV=test mix test
env:
  ELIXIR_VERSION: 1.1.1
  ELIXIR_VERSION: 1.2.0-rc.0