Added support for symfony 4 single deps

* fix composer.json and travis

.travis.yml

@@ -17,7 +17,20 @@ matrix:
         SYMFONY_VERSION=^4.0
 
 before_install:
-  - sh -c 'if [ "${SYMFONY_VERSION}" != "" ]; then composer require --no-update symfony/symfony=${SYMFONY_VERSION}; fi;';
+  - |
+    if [ "${SYMFONY_VERSION}" != "" ]; then
+      packages="form dependency-injection config http-foundation http-kernel options-resolver security serializer"
+      devpackages="framework-bundle browser-kit templating expression-language"
+      for package in $packages
+        do
+          composer require --no-update symfony/"$package"=${SYMFONY_VERSION};
+         done
+      for package in $devpackages
+        do
+          composer require --dev --no-update symfony/"$package"=${SYMFONY_VERSION};
+        done
+    fi;
+
 
 before_script:
   - echo "extension=mongodb.so" >> `php --ini | grep "Loaded Configuration" | sed -e "s|.*:\s*||"`

composer.json

@@ -21,10 +21,21 @@
     ],
     "require": {
         "php": ">=5.6",
-        "symfony/symfony": "~2.8|~3.0|^4.0",
+        "symfony/form": "~2.8|~3.0|^4.0",
+        "symfony/dependency-injection": "~2.8|~3.0|^4.0",
+        "symfony/config": "~2.8|~3.0|^4.0",
+        "symfony/http-foundation": "~2.8|~3.0|^4.0",
+        "symfony/http-kernel": "~2.8|~3.0|^4.0",
+        "symfony/options-resolver": "~2.8|~3.0|^4.0",
+        "symfony/security": "~2.8|~3.0|^4.0",
+        "symfony/serializer": "~2.8|~3.0|^4.0",
         "twig/twig": ">=1.5.0"
     },
     "require-dev": {
+        "symfony/framework-bundle": "~2.8|~3.0|^4.0",
+        "symfony/browser-kit": "~2.8|~3.0|^4.0",
+        "symfony/templating": "~2.8|~3.0|^4.0",
+        "symfony/expression-language": "~2.8|~3.0|^4.0",
         "phpunit/phpunit": "~5.7",
         "friendsofphp/php-cs-fixer": "^2.0",
         "satooshi/php-coveralls": "^1.0",