Pin to stable versions

- Updated PHP minimum version to 5.6.
- Marked zend-mvc < 3.0.0 as a conflict.

.travis.yml

@@ -25,15 +25,6 @@ env:
 matrix:
   fast_finish: true
   include:
-    - php: 5.5
-      env:
-        - DEPS=lowest
-    - php: 5.5
-      env:
-        - DEPS=locked
-    - php: 5.5
-      env:
-        - DEPS=latest
     - php: 5.6
       env:
         - DEPS=lowest

composer.json

@@ -9,7 +9,7 @@
     ],
     "homepage": "https://github.com/zendframework/zend-mvc-i18n",
     "require": {
-        "php": "^5.5 || ^7.0",
+        "php": "^5.6 || ^7.0",
         "container-interop/container-interop": "^1.1",
         "zendframework/zend-i18n": "^2.7",
         "zendframework/zend-router": "^3.0",
@@ -25,6 +25,9 @@
     "suggest": {
         "zendframework/zend-cache": "To enable caching of translation strings"
     },
+    "conflict": {
+        "zendframework/zend-mvc": "<3.0.0"
+    },
     "autoload": {
         "psr-4": {
             "Zend\\Mvc\\I18n\\": "src/"