language: c
sudo: required
dist: trusty
install: wget https://raw.githubusercontent.com/ocaml/ocaml-ci-scripts/master/.travis-opam.sh
script: bash .travis-extra-deps.sh
env:
  global:
    - POST_INSTALL_HOOK="bash .travis-test-compile.sh"
  matrix:
    - OCAML_VERSION=4.03
    - OCAML_VERSION=4.06
    - OCAML_VERSION=4.07
os:
  - linux
  - osx
addons:
  apt:
    update: true

language: c
sudo: required
dist: xenial
install: wget https://raw.githubusercontent.com/ocaml/ocaml-ci-scripts/master/.travis-opam.sh
script: bash .travis-extra-deps.sh
env:
  global:
    - POST_INSTALL_HOOK="bash .travis-test-compile.sh"
  matrix:
    - OCAML_VERSION=4.03
    - OCAML_VERSION=4.06
    - OCAML_VERSION=4.07
os:
  - linux
  - osx
addons:
  apt:
    update: true

Update Travis to use Ubuntu/Xenial
Update Travis to use Ubuntu/Xenial

Maybe this will fix the gnutls errors, e.g.

    Error downloading 'https://downloads.sourceforge.net/project/zero-install/0install/2.14/0install-linux-x86_64-2.14.tar.bz2': gnutls_handshake() failed: Handshake failed
