[Travis] Enabled OPCache, composer prefers dist during install

.travis.yml

@@ -14,25 +14,24 @@ cache:
 
 sudo: false
 
-services:
-    - memcached
-
 matrix:
     fast_finish: true
 
     include:
         - php: 5.6
           env: TEST_SUITE=no-javascript
-          services: [mongodb]
+          services: [memcached, mongodb]
         - php: 5.6
           env: TEST_SUITE=javascript
+          services: [memcached]
           sudo: required
 
         - php: 7.0
           env: TEST_SUITE=no-javascript
+          services: [memcached]
         - php: 5.5
           env: TEST_SUITE=no-javascript
-          services: [mongodb]
+          services: [memcached, mongodb]
 
 before_install:
     - mkdir -p $SYLIUS_CACHE_DIR
@@ -47,10 +46,12 @@ before_install:
 
     - if [ $TRAVIS_PHP_VERSION != "7.0" ] && [ $TEST_SUITE = "no-javascript" ]; then travis/prepare/prepare-mongodb; fi
 
-    - composer install --prefer-source --no-interaction
+    - composer install --prefer-dist --no-interaction
 
     - if [ $TEST_SUITE = "javascript" ]; then travis/prepare/prepare-javascript; fi
 
+    - cat travis/prepare/opcache.ini >> ~/.phpenv/versions/$(phpenv version-name)/etc/php.ini
+
 before_script:
     - app/console doctrine:database:create --env=test
     - app/console doctrine:schema:create --env=test

travis/prepare/mongodb/2-rebuild-cache

@@ -1,3 +1,3 @@
 #!/bin/bash
 
-composer require doctrine/mongodb-odm="^1.0.2"
+composer require --prefer-dist doctrine/mongodb-odm="^1.0.2"

travis/prepare/opcache.ini

@@ -0,0 +1,10 @@
+; May help to speed up our test suites
+[opcache]
+opcache.enable = 1
+opcache.enable_cli = 1
+
+opcache.memory_consumption = 128
+opcache.max_accelerated_files = 4000
+opcache.revalidate_freq = 60
+opcache.save_comments = 1
+opcache.fast_shutdown = 1