Update Appveyor and Travis CI environment

[larskanis]

• Update to codeclimate-test-reporter-1.0
• Add latest Windows MRI versions
• Add latest Linux MRI and rbx versions
• Use faster docker based environment on travis-ci
• Force overwriting of possible binstubs of bundler
• Add workaround for bundler on rbx (missing constant Bundler::Deprecate)
• Add rbx to allow_failures, since it's not very stable nowadays
• Remove manual bundle install, it is called by travis-ci already

[larskanis]

It seems that Appveyor isn't enabled for this repository. If you enable it, it should work.

[deadprogram]

I just enabled Appveyor @larskanis now merging this PR. Thank you!