raise requirements to PHP 7.2 and WordPress 5.0

composer.json

@@ -1,6 +1,6 @@
 {
   "name": "stklcode/stklcode-liveticker",
-  "version": "1.2.2",
+  "version": "1.3.0",
   "description": "A simple Liveticker for Wordpress.",
   "keywords": [
     "wordpress",
@@ -17,14 +17,14 @@
   ],
   "type": "wordpress-plugin",
   "require": {
-    "php": ">=5.6",
-    "composer/installers": "~1.12"
+    "php": ">=7.2",
+    "composer/installers": "~v2.1.1"
   },
   "require-dev": {
     "dealerdirect/phpcodesniffer-composer-installer": "^v1.0",
     "matthiasmullie/minify": "^1.3",
     "phpcompatibility/phpcompatibility-wp": "^2.1",
-    "phpunit/phpunit": "^5|^6|^7|^8|^9",
+    "phpunit/phpunit": "^8|^9",
     "slowprog/composer-copy-file": "~0.3",
     "squizlabs/php_codesniffer": "^3.9",
     "wp-coding-standards/wpcs": "^3.0",