Add Github Actions

Author: micheh

.github/workflows/verify.yml

@@ -0,0 +1,38 @@
+name: Verify
+
+on: [push, pull_request]
+
+jobs:
+  phpcs:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: shivammathur/setup-php@v1
+        with:
+          php-version: 7.3
+          coverage: none
+          tools: cs2pr
+
+      - name: Install dependencies
+        run: composer install
+        
+      - name: Run PHP Codesniffer
+        run: vendor/bin/phpcs --report=checkstyle -q | cs2pr
+        
+  phpstan:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: shivammathur/setup-php@v1
+        with:
+          php-version: 7.3
+          coverage: none
+          tools: cs2pr
+
+      - name: Install dependencies
+        run: composer install
+        
+      - name: Run PHPStan
+        run: vendor/bin/phpstan analyse --error-format=checkstyle | cs2pr