feat: grenrc definition (#13)

.grenrc.js

@@ -0,0 +1,30 @@
+module.exports = {
+  "dataSource": "prs",
+  "prefix": "",
+  "onlyMilestones": false,
+  "groupBy": {
+    "Enhancements": [
+      "enhancement",
+      "internal"
+    ],
+    "Bug Fixes": [
+      "bug"
+    ],
+    "Documentation": [
+      "documentation"
+    ],
+    "Others": [
+      "other"
+    ]
+  },
+  "changelogFilename": "CHANGELOG.md",
+  "template": {
+      commit: ({ message, url, author, name }) => `- [${message}](${url}) - ${author ? `@${author}` : name}`,
+      issue: "- {{name}} [{{text}}]({{url}})",
+      noLabel: "other",
+      group: "\n#### {{heading}}\n",
+      changelogTitle: "# Changelog\n\n",
+      release: "## {{release}} ({{date}})\n{{body}}",
+      releaseSeparator: "\n---\n\n"
+  }
+}