Update README with info on Metrics cops

Forgotten in earlier PR.
Merge pull request #1234 from jonas054/update_readme_metrics

Update README with info on Metrics cops
Make Debugger cop also check for `binding.pry_remote`

Because `pry_remote` is an alias for `remote_pry`.
https://github.com/Mon-Ouie/pry-remote/blob/2557d39e003450a7fc11d4c3e48cc3eb5b01302d/lib/pry-remote.rb#L349
Mention that the README tracks the master branch
Merge pull request #1237 from yous/patch-pry-remote

Make Debugger cop also check for `binding.pry_remote`
Revert "Add json gem as a runtime dependency for Ruby 1.9.2"

This reverts commit 71ad28d77749eccbbe52034c7909bdfd8f266a8f.

Conflicts:
	rubocop.gemspec
Revert "Test against Ruby 1.9.2 on Travis CI"

This reverts commit 9d90af624c9c45777359124e3bd497f75f84f69e.
Bump required Ruby version to 1.9.3
Update README and changelog
Merge pull request #1194 from yujinakayama/drop-support-for-ruby-1.9.2

Drop support for Ruby 1.9.2