Add import/no-cycle

[amannn]

https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-cycle.md

[amannn]

The rule is apparently quite computationally expensive and I'm a bit hesitant to add it, since bundlers have some support for circular imports. I'd wait if we run into this problem again before enabling this.