Automated testing with Luacheck (#533)

.github/workflows/main.yml

@@ -0,0 +1,12 @@
+name: Luacheck
+on: [push]
+jobs: 
+  Luacheck_Tests:
+    runs-on: ubuntu-latest
+    steps:
+      - run: echo "Running tests triggered by a ${{ github.event_name }} event."
+      - run: echo "Testing ${{ github.ref }} from ${{ github.repository }} on ${{ runner.os }}"
+      - name: Check out code
+        uses: actions/checkout@v3
+      - name: Run tests
+        uses: lunarmodules/luacheck@v0 

.luacheckrc

@@ -0,0 +1,11 @@
+codes = true
+allow_defined = true
+max_line_length = false
+
+globals = {
+    "client", "screen", "mouse"
+}
+
+ignore = {
+    "131",
+}