Set required ruby version
Fix README

When `handle_exceptions` is disabled, we just raise every exception.
Small documentation fix
Fix parameter name in documentation

The parameter name is `formats`, not `mime_types`.
Document redirect with custom status code
Merge pull request #24 from joneslee85/patch-1

Set required ruby version
Merge pull request #27 from arthurgeek/patch-1

Fix README
Merge pull request #29 from arthurgeek/patch-3

Small documentation fixes
Merge pull request #30 from arthurgeek/document_redirect_custom_status_code

Document redirect with custom status code
Added JRuby to the allowed failures of the CI. Ref jruby/jruby#751