small refactoring
upgrade rspec, make knife-solo a development dep
tests for bootstrapping
remove jruby as chef itself doesn't run on jruby
updated changelog
Update README.md
Revert "small refactoring"

see https://github.com/rmoriz/knife-digital_ocean/commit/28a997e3e984fa6f429e825349077c0e9745442e

This reverts commit 28a997e3e984fa6f429e825349077c0e9745442e.
prepare release
Update CHANGELOG.md