Added GrumPHP configuration

Author: frenck

grumphp.yml

@@ -0,0 +1,15 @@
+parameters:
+    git_dir: .
+    bin_dir: vendor/bin
+    tasks:
+      jsonlint:
+        detect_key_conflicts: true
+      composer: ~
+      yamllint: ~
+      securitychecker: ~
+      git_conflict: ~
+      npm_script:
+        script: "test"
+        triggered_by: [md]
+        working_directory: "./"
+        is_run_task: true