Add eslint 5 support

[noqcks]

I've upgrade to eslint 5 and upgraded some packages that support eslint5.

How has it been checked previously whether external dependencies support eslint version x? For example, for the eslint 4 branch? For me I checked whether eslint5 was in the dev dependencies for 3rd party dependencies, but this can produce some false negatives.

I've opened this PR up against the channel/eslint-4 branch because I am unable to create the channel/eslint-5 branch.

[modosc]

i'm happy to help if there's anything left to do here.

[noqcks]

Thanks @modosc just waiting on a review from someone on the codeclimate team.

We might have some unsupported dependencies in eslint5 that we'll have to remove.

cc: @efueger @wfleming

[filipesperandio]

@noqcks Sorry this is taking long. I've just pushed the channel/eslint-5 branch and updated to PR against it. I will do some testing next and let you know.

[noqcks]

no worries! @filipesperandio

thanks for taking a look 🙏

[noqcks]

@filipesperandio I remember the reason why I removed eslint-config-secure

CI is throwing the error I was getting locally

error An unexpected error occurred: "could not find a copy of eslint to link in /usr/local/node_modules/eslint-config-secure/node_modules".

[noqcks]

Thanks @filipesperandio !!

If all goes well, how do I know once eslint5 becomes available on the codeclimate platform? Keep an eye on the changelog?

[filipesperandio]

Will be updating that soon, though, I've just merged PRs enabling it, so the channel should be available soon.