Merge pull request #311 from moririnson/feature/stop-support-5.5

Update lib versions

Author: moririnson

composer.json

@@ -38,10 +38,9 @@
     "ext-sockets": "*"
   },
   "require-dev": {
-    "phpunit/phpunit": "^4.8.24||^5||^6",
-    "phpmd/phpmd": "~2.4",
-    "squizlabs/php_codesniffer": "~2.6||^3",
-    "indigophp/hash-compat": "~1.1.0",
+    "phpunit/phpunit": "^4.8.36||^5||^6||^7",
+    "phpmd/phpmd": "~2.9",
+    "squizlabs/php_codesniffer": "~3.5",
     "ext-posix": "*"
   },
   "suggest": {