update dependency versions

- php: >= 7.1.3
- piece/stagehand-fsm: >= 2.5.0
- symfony/expression-language: >= 3.4.0 or >= 4.0.0
- phpunit/phpunit: >= 5.0.0

.travis.yml

@@ -7,7 +7,6 @@ cache:
     - $HOME/.composer/cache
 
 php:
-  - 7.0
   - 7.1
   - 7.2
 

composer.json

@@ -11,15 +11,15 @@
         }
     ],
     "require": {
-        "php": ">=7.0.8",
+        "php": "^7.1.3",
         "ext-dom": "*",
         "phpmentors/domain-kata": "~1.4",
-        "piece/stagehand-fsm": "~2.5",
-        "symfony/expression-language": "~2.8 || ~3.0"
+        "piece/stagehand-fsm": "~2.6",
+        "symfony/expression-language": "~3.4|~4.0"
     },
     "require-dev": {
         "phake/phake": "~2.0",
-        "phpunit/phpunit": "~4.0"
+        "phpunit/phpunit": "~5.0"
     },
     "autoload": {
         "psr-4": {

docker-compose.yml.dist

@@ -2,7 +2,7 @@ version: '2'
 services:
     app:
         container_name: "phpmentors.workflower.app"
-        image: "phpmentors/php-app:php70"
+        image: "phpmentors/php-app:php71"
         volumes:
             - ".:/var/app"
         environment: