Build and CI configuration update

Author: remorhaz

.travis.yml

@@ -1,12 +1,12 @@
 language: php
 
 php:
-  - '7.0'
   - '7.1'
+  - '7.2'
 
 before_script:
   - composer self-update
-  - composer install --prefer-source --no-interaction --dev
+  - composer install --prefer-source --no-interaction
 
 script: phpunit
 

composer.json

@@ -12,12 +12,12 @@
     }
   ],
   "require": {
-    "php": ">=7.0",
-    "remorhaz/php-json-data": "~0.3.0",
-    "remorhaz/php-json-pointer": "~0.4.0"
+    "php": ">=7.1",
+    "remorhaz/php-json-data": "~0.4.2",
+    "remorhaz/php-json-pointer": "~0.5.0"
   },
   "require-dev": {
-    "phpunit/phpunit": "~6.1",
+    "phpunit/phpunit": ">=7.0.1 <8.0",
     "codeclimate/php-test-reporter": "dev-master"
   },
   "autoload": {