Refactors to use a response factory instead of prototype

Updates to use a response factory instead of a prototype. This
alleviates the need for a stream factory, and allows re-use of the
`ResponseInterface` service with Expressive v3. It also simplifies the
constructors.

Author: weierophinney

composer.json

@@ -25,15 +25,15 @@
     },
     "require": {
         "php": "^7.1",
+        "http-interop/http-middleware": "^0.5.0",
         "psr/http-message": "^1.0.1",
         "psr/http-message-implementation": "^1.0",
         "psr/link": "^1.0",
         "willdurand/negotiation": "^2.3.1"
     },
     "require-dev": {
-        "phpunit/phpunit": "^6.4.3",
+        "phpunit/phpunit": "^7.0.1",
         "zendframework/zend-coding-standard": "~1.0.0",
-        "zendframework/zend-diactoros": "^1.6",
         "zendframework/zend-expressive-helpers": "^4.2 || ^5.0.0-dev || ^5.0.0",
         "zendframework/zend-hydrator": "^2.3.1",
         "zendframework/zend-paginator": "^2.7"