Install rsync on CI

Thanks @joshlambert
https://gitlab.slack.com/archives/ci/p1486416829005766

.gitlab-ci.yml

@@ -16,7 +16,7 @@ before_script:
   # -----------------------------------------------------------
   # Install ssh-agent if not already installed, it is required by Docker.
   # (change apt-get to yum if you use a CentOS-based image)
-  - 'which ssh-agent || ( apt-get update -y && apt-get install openssh-client -y )'
+  - 'which ssh-agent || (apt-get update -y && apt-get install openssh-client -y)'
   # Run ssh-agent (inside the build environment)
   - eval $(ssh-agent -s)
   # Add the SSH key stored in SSH_PRIVATE_KEY variable to the agent store
@@ -27,6 +27,9 @@ before_script:
   # you will overwrite your user's SSH config.
   - mkdir -p ~/.ssh
   - '[[ -f /.dockerenv ]] && echo -e "Host *\n\tStrictHostKeyChecking no\n\n" > ~/.ssh/config'
+  # Install rsync
+  # --------
+  - which rsync || (apt-get update -y && apt-get install rsync -y)
 build: