Cannot pass ESLint validation

[tylerlong]

Ideally, ESLint validation should be added to CI.

[u9520107]

@tylerlong We actually are using codacy to check these at the moment, but we have not yet started to enforce these rules, nor have we really discussed the rule sets at this stage. Ideally, any new code we check in pass the codacy check, and we should also start to make sure old code start to conform to these rules. Quite frankly I don't think we'll just do this in one step and make every file pass this test at the moment.