Migrate remaining non-counter rules to counters

[khiga8]

Fixes: #48

What?

Sorry for the big diff! It comes from the file renames and adding a couple of the same tests.

This completes migration of the remaining 5 non-counter rules:

• Swaps rule_disabled? code with counter_correct? code
• Add autocorrect support.
• Add counter test cases to existing test.
• Rename rules to include counter.

Why?

Counters have better disable functionality. These remaining 5 rules are in "legacy" format and I think it'll be confusing for new people trying to introduce this plugin to their project that we have a erblint:disable format and an erblint:counter format.

I am trying to complete this migration to better enable one of our teams who are in the process of enabling this plugin in their repo :).

With these changes, a codebase newly enabling this plugin can run:

bundle exec erblint app/views -a

to add the disable comments wherever necessary.

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