Allow PHP 7.3 and higher

Author: legendik

.travis.yml

@@ -1,13 +1,13 @@
 language: php
 php:
-    - 7.1
-    - 7.2
+    - 7.3
+    - 7.4
 
 matrix:
   include:
-    - php: 7.1
+    - php: 7.3
       env: DEPENDENCIES="--prefer-lowest"
-    - php: 7.2
+    - php: 7.4
       env: CHECK_CODESTYLE=1
       before_install: phpenv config-rm xdebug.ini
       before_script:

composer.json

@@ -13,7 +13,7 @@
         }
     },
     "require": {
-        "php": "^7.1",
+        "php": "^7.3",
         "ext-mbstring": "*",
         "beberlei/assert": "^2.9 || ^3.0",
         "mf/collections-php": "^4.0"