Merge pull request #86 from basz/relax-dependency

remove zend-expressive as it is not required

composer.json

@@ -18,18 +18,14 @@
   ],
   "require": {
     "php": ">=7.0",
-    "zendframework/zend-diactoros": "~1.1",
+    "zendframework/zend-diactoros": "^1.1",
     "psr/container": "^1.0",
     "ramsey/uuid": "^3.1"
   },
   "require-dev": {
     "friendsofphp/php-cs-fixer": "^2.1",
     "phpunit/phpunit": "^6.0",
-    "satooshi/php-coveralls": "~1.0",
-    "zendframework/zend-stratigility": "~1.1"
-  },
-  "suggest": {
-    "zendframework/zend-stratigility": "~1.1 : if you need the middleware capability"
+    "satooshi/php-coveralls": "~1.0"
   },
   "autoload": {
     "psr-4": {