Support the ESLint Suggestions API

[sindresorhus]

There have been many cases where we could not provide auto-fixers because it was either not safe or there were multiple possible fixes. The Suggestions API enables us to provide multiple fixes that can be manually chosen by a user in an editor.

We should go through existing rules with no auto-fixers or with incomplete auto-fixers and make them support the Suggestions API.

[sindresorhus]

I suggest (pun intended) that we drop auto-fixer for the no-only-test and no-skip-test and instead implement suggestions for them. Auto-fixers for those can be annoying (xojs/vscode-linter-xo#78) when you have "fix on save" in an editor.

@novemberborn Thoughts?

[novemberborn]

Agreed.