New: some core rules for <template>

[mysticatea]

This PR proposes to add the wrappers of some core rules to apply those to the expressions in <template>.

• array-bracket-spacing
• eqeqeq
• key-spacing
• object-curly-spacing
• space-infix-ops
• space-unary-ops

Those are simple wrappers. For example:

const { wrapCoreRule } = require('../utils')
module.exports = wrapCoreRule(require('eslint/lib/rules/array-bracket-spacing'))

It would be useful for styling embedded expressions.

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Probably I need to separate PRs per rule.

[armano2]

should we keep meta.url from eslint or should we override it to our doc?

{ docs: Object.assign({}, coreRule.meta.docs, { category }) }

replaces #599

[mysticatea]

I updated to override meta.docs.url.

[ota-meshi]

Awesome!

[michalsnik]

@mysticatea would you mind updating docs? And we could proceed with this :) Sorry for slow response here..

[mysticatea]

I updated this PR for conflictions.

[michalsnik]

LGTM, thanks 👍

[mrleblanc101]

Maybe you should consider showing a warning that these rules are not yet available in the latest version of the plugin since it was release 9 days ago and this was merged 6 days ago ?
I've spend many hours yesterday figuring out why 😞