Add code coverage

[dojutsu-user]

1. Code coverage might be good addition to show the percentage of code tested.
2. A codecov badge can be added to the README.

https://codecov.io/ can be used for this.

[Divy123]

I think this can be great to implement.
This can help us a lot to write tests and and know our code coverage.
@jywarren thoughts?
If sounds cool, I would love to implement this one.
Thanks @dojutsu-user for opening this issue.

[jywarren]

this would be fantastic, would you be interested in opening a PR for this?

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On Thu, Feb 14, 2019 at 1:44 PM Vaibhav Gupta ***@***.***> wrote: 1. Code coverage might be good addition to show the percentage of code tested. 2. A codecov badge can be added to the README. https://codecov.io/ can be used for this. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#774>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AABfJw7KI41MUI0auXcmnYkWRGpb0EaYks5vNa53gaJpZM4a8NLJ> .

[Divy123]

Sure I will be opening a PR soon..

[jywarren]

Also noting: https://docs.codeclimate.com/docs/travis-ci-test-coverage could work for this...

and I believe this is needed? https://libraries.io/npm/codeclimate-test-reporter

[jywarren]

Also linking to https://github.com/publiclab/image-sequencer/pull/929/files!