Add luacheck in CI

[madmaxoft]

Luacheck should be added as another test in the CI.

[Seadragon91]

This are my current changes in CuberitePluginChecker.
I added the file .lauchecrc, install and run luacheck. The file will be added to the plugin directory if the plugin doesn't contain it.

[Seadragon91]

Current result from circleci.

Edit: The q flag filters out files from output, where luacheck doesn't detect any problems.

[madmaxoft]

This is not what I had in mind when creating this issue. I wanted LuaCheck to actually check this repo, not another plugin. Adding LuaCheck to other plugins is a matter of those plugins, not CuberitePluginChecker.

Also, the CI script is malformed now - consider that all actions listed in the test/override section can be run in parallel next to each other. All the setup needed for the test needs to be done on a single line.

[Seadragon91]

Ah okay sorry, will create a pull request that adds luacheck and we can discuss there about correcting problems in CuberitePluginChecker.