Update Composer, update everything

vendor/stecman/symfony-console-completion/.travis.yml

@@ -0,0 +1,28 @@
+language: php
+
+matrix:
+  include:
+    - php: 5.4
+    - php: 5.5
+      env: COMPOSER_OPTS="--prefer-lowest"
+    - php: 5.6
+    - php: 7.0
+    - php: 7.1
+    - php: 7.2
+    - php: nightly
+    - php: hhvm
+      env: COMPOSER_OPTS="--prefer-lowest"
+
+  allow_failures:
+    - php: nightly
+
+before_install:
+  - sudo apt-get update -qq
+  - sudo apt-get install -y bash zsh
+
+install:
+  - composer self-update
+  - composer update $COMPOSER_OPTS
+
+script:
+  - vendor/bin/phpunit