Add LUA linting

.drone.yml

@@ -17,7 +17,7 @@ steps:
   commands:
     - apk update
     - apk add --no-cache wget lua5.1 lua5.1-dev luarocks5.1
-    - luarocks-5.1 install luacheck
+    - luarocks-5.1 install --verbose luacheck
     - luacheck sources
 
 - name: build