adjust a few signatures to accommodate new alpha deps

Author: ashnazg

composer.json

@@ -18,16 +18,16 @@
             ]
         }
     },
+    "minimum-stability": "alpha",
     "require": {
         "php": ">=7.1",
         "psr/log": "~1.0",
         "nikic/php-parser": "^3.0",
-        "phpdocumentor/reflection-docblock": "^4"
+        "phpdocumentor/reflection-docblock": "^5"
     },
     "require-dev": {
         "mockery/mockery": "~1.0",
-        "mikey179/vfsStream": "~1.2",
-        "phpunit/phpunit": "~6.5"
+        "mikey179/vfsStream": "~1.2"
     },
     "extra": {
         "branch-alias": {