Add new RSpec/EmptyHooks cop

[tejasbubane]

Closes #811

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Before submitting the PR make sure the following are checked:

• Feature branch is up-to-date with master (if not - rebase it).
• Squashed related commits together.
• Added tests.
• Updated documentation.
• Added an entry to the changelog if the new code introduces user-observable changes.
• The build (bundle exec rake) passes (be sure to run this locally, since it may produce updated documentation that you will need to commit).

If you have created a new cop:

• Added the new cop to config/default.yml.
• The cop documents examples of good and bad code.
• The tests assert both that bad code is reported and that good code is not reported.

[pirj]

Looks good, thank you!
A few things can be improved in the cop itself, and the spec might be made more human-readable.

[pirj]

Ping

[tejasbubane]

@pirj Fixed. Please review.

[pirj]

Looks incredible, good job!

A few really minor notes concerning simplification.

[tejasbubane]

@pirj Changes done.

[Darhazer]

You can add autocorrect that removes the offending node

[pirj]

👍 Thank you!

[bquorning]

You can add autocorrect that removes the offending node

Do you want to give it a shot, @tejasbubane? Otherwise let’s open a new issue so we don’t forget to implement it.

[tejasbubane]

@bquorning I have added autocorrect.

[bquorning]

Thank you

[bquorning]

I’d like a second review from @pirj or @Darhazer before merging.

[pirj]

All good.

Just in case maybe add a spec covering the case with semicolon?

[tejasbubane]

@pirj Added spec for semicolon - it is a little ugly though - since it does not remove the semicolon.

[pirj]

Added spec for semicolon - it is a little ugly though - since it does not remove the semicolon.

No worries, it's less ugly than before {}; after { delete_users } 😄