fix: Updating dependencies (#125)

Author: aliabbasrizvi

Diff for: composer.json

@@ -11,15 +11,15 @@
   ],
   "require": {
     "php": ">=5.5",
-    "justinrainbow/json-schema": "^1.6 || ^2.0 || ^4.0",
+    "justinrainbow/json-schema": "^1.6 || ^2.0 || ^4.0 || ^5.0",
     "lastguest/murmurhash": "1.3.0",
     "guzzlehttp/guzzle": "~5.3|~6.2",
     "monolog/monolog": "~1.21",
     "icecave/parity": "^1.0"
   },
   "require-dev": {
-    "phpunit/phpunit": "~4.8|~5.0",
-    "satooshi/php-coveralls": "v1.0.1"
+    "phpunit/phpunit": "^4.8|^5.0",
+    "php-coveralls/php-coveralls": "v2.0.0"
   },
   "autoload": {
     "psr-4": {