Fix .travis.yml

Author: alexsibtihon

.travis.yml

@@ -9,38 +9,40 @@ cache:
     - $HOME/.composer/cache
 
 php:
-  - 5.4
-  - 5.5
   - 5.6
   - 7.0
   - 7.1
+  - 7.2
   - hhvm
 
 env:
   global:
     - TEST_COMMAND="composer test"
-    - DOCKER_VERSION=1.12.0-0~trusty
+    - DOCKER_VERSION=18.03.0~ce-0~ubuntu
 
 matrix:
   allow_failures:
     - php: hhvm
   fast_finish: true
   include:
-    - php: 5.4
+    - php: 5.6
       sudo: required
       services:
-          - docker
+        - docker
       env: COMPOSER_FLAGS="--prefer-stable --prefer-lowest" COVERAGE=true TEST_COMMAND="composer test-ci"
 
 before_install:
-  - sudo apt-cache madison docker-engine
-  - sudo apt-get -o Dpkg::Options::="--force-confnew" install -y --force-yes docker-engine=${DOCKER_VERSION}
+  - sudo apt-get update
+  - curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
+  - sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
+  - sudo apt-get update
+  - sudo apt-cache madison docker-ce
+  - sudo apt-get -o Dpkg::Options::="--force-confnew" install -y --force-yes docker-ce=${DOCKER_VERSION}
   - travis_retry composer self-update
 
 install:
-  - travis_retry composer update ${COMPOSER_FLAGS} --prefer-source --no-interaction
-  - docker pull registry:latest
-  - docker run -p 5000:5000 -d registry
+  - travis_retry composer install
+  - travis_retry composer update ${COMPOSER_FLAGS} --no-interaction
 
 script:
   - $TEST_COMMAND