hotfix travis composer

Author: zonky2

.travis.yml

@@ -1,17 +1,19 @@
 language: php
 
 php:
-  - "5.4"
-  - "5.5"
-  - "5.6"
-  - "7.0"
+  - "7.2"
   - "7.1"
+  - "7.0"
+  - "5.6"
 
 env:
   - CONTAO_VERSION=~3.5.5
 
 sudo: false
 
+before_install:
+  - echo "memory_limit = -1" > travis.php.ini && phpenv config-add travis.php.ini
+
 install:
   - travis_retry composer self-update && composer --version
   - travis_retry composer require contao/core $CONTAO_VERSION --no-update
@@ -22,3 +24,7 @@ script: ant -keep-going
 # Hack to make things work again - we can not use a shallow repository.
 git:
   depth: 2147483647
+
+cache:
+  directories:
+    - vendor

composer.json

@@ -9,7 +9,7 @@
   ],
   "type": "contao-module",
   "homepage": "http://now.metamodel.me/",
-  "license": "LGPL-3.0+",
+  "license": "LGPL-3.0-or-later",
   "authors": [
     {
       "name": "Christian Schiffler",
@@ -31,7 +31,7 @@
     "source": "https://github.com/MetaModels/filter_range"
   },
   "require": {
-    "php": ">=5.4",
+    "php": "^5.6 || ^7.0",
     "contao/core": "^3.5.5",
     "contao-community-alliance/composer-plugin": "~2.0",
     "metamodels/core": "~2.0"