Add Dangerfile.swift

Signed-off-by: Joseph Mattello <mail@joemattiello.com>

.github/workflows/danger.yml

@@ -0,0 +1,13 @@
+name: "Danger Swift"
+on: [pull_request]
+
+jobs:
+  build:
+    name: Danger JS
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+      - name: Danger Swift
+        uses: danger/swift@2.0.3
+    env:
+      GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}