Improve CodeClimate config

[artur-intech]

Nothing to test.

• Show all offences
• Use shared rubocop.yml
• Remove customizations
• Remove unneeded gems

[maciej-szlosarczyk]

Loads of work to do.

[artur-intech]

Definitely. Before there was .rubocop-to-do file, regenerated based on issues at the time of generation, but I found that this approach just doesn't work. You need to either find&replace file/folder names and/or regenerate it as long you fix something. It's more effort than benefit. Let's try to minimize the amount of issues with every next change.

I think it's better to be honest with ourselves and have all problems clearly defined.

[artur-intech]

What I would do, is remove this badge from project's front page. It's a bit awkwardly to "start a book with erratum".
http://prntscr.com/jqkgw5

[vohmar]

code climate seems stuck with analysis

[maciej-szlosarczyk]

I restarted the thing, the check is complete now.

[artur-intech]

@vohmar So how about removing that badge (see a comment above)?

[vohmar]

@artur-beljajev as we discussed, lets leave the badge as is - removing it does not improve anything except hinding the current state of things from general public. It's an open source project - lets be open.