Crossplatform grep

Author: Tofandel

composer.json

@@ -57,7 +57,7 @@
             "pre-commit": "composer check-style",
             "pre-push": [
                 "composer test",
-                "appver=$(grep -o -P '\\d+\\.\\d+\\.\\d+(-alpha\\.\\d+)?' cghooks)",
+                "appver=$(grep -o -E '[0-9]+\\.[0-9]+\\.[0-9]+(-alpha\\.[0-9]+)?' cghooks)",
                 "tag=$(git tag | tail -n 1)",
                 "if [ \"$tag\" != \"v$appver\" ]; then",
                 "echo \"The most recent tag $tag does not match the application version $appver\\n\"",