Fixes #12530 - Upgrade rubocop to 0.35.1

[daviddavis]

This is mostly because of improved problem detection. A couple cops have bugs that cause false positives and negatives. There are also some new cops I'd like to enable like Lint/DuplicateMethods but will do so after we upgrade to Rails 4

[domcleal]

Are the disabled cops all of the new ones, or just all of the new ones that fail in some way? (Missing offence counts.)

It might be preferable to refresh the todo file from --auto-gen-config, so we get to use the new cops for future changes and keep them disabled only where there are existing problems? e.g. cops such as Performance/Detect are valuable.

[daviddavis]

These are just the new cops that are failing. In rubocop 0.33.0 they changed --auto-gen-config to exclude files that have problems instead of disabling the cops altogether (see https://github.com/fusor/fusor/pull/465/files). This effectively turns on the cop for any new code. I'm not sure I like that.

However, it looks like I can generate the todo file with cops being disabled by using --exclude-limit 0. I've updated the PR with this so we can get the offense counts.

Let me know if you prefer excluding files over disabling outstanding cops.

[dLobatog]

Glad to see we decreased the max since Rubocop was added 😄

[dLobatog]

@daviddavis Rubocop is complaining about the length of 2 classes (no kidding), I'd say 👍 after fixing that.

[daviddavis]

@dLobatog thanks. Should be fixed now.

[domcleal]

Let me know if you prefer excluding files over disabling outstanding cops.

Yes, I did prefer the exclusion of files, so we get the benefit of some cops on new code - though I guess I was particularly interested in the performance ones, less that we should enforce different style. Should we make that distinction?

[daviddavis]

@domcleal updated. thanks.

[domcleal]

Merged as a9d8cde, thanks @daviddavis.