change license note in composer.json

composer.json

@@ -19,7 +19,7 @@
   ],
   "homepage": "https://www.oxidmodule.com/",
   "license": [
-    "proprietary"
+    "GPL-3.0-or-later"
   ],
   "extra": {
     "oxideshop": {
@@ -31,7 +31,7 @@
     }
   },
   "require": {
-    "php": ">=5.6",
+    "php": "^7.0",
     "oxid-esales/oxideshop-ce": "6.3 - 6.5",
     "spipu/html2pdf": "^5.2"
   },