Added support for lexer ^2.0 (#458)

Author: norberttech

composer.json

@@ -21,9 +21,10 @@
         "ext-simplexml": "*",
         "aeon-php/calendar": "^0.14.0 || ^0.15.0 || ^0.16.0 || ^0.17.0 || ^0.18.0 || ^1.0",
         "coduo/php-to-string": "^3",
-        "doctrine/lexer": "^1.0"
+        "doctrine/lexer": "^1.0||^2.0"
     },
     "require-dev": {
+        "ext-pcov": "*",
         "openlss/lib-array2xml": "^1.0",
         "symfony/expression-language": "^2.3|^3.0|^4.0|^5.0"
     },