Add gems for testing.
Add cucumber environment, helpers and step definitions.

This took a lot longer to make than this commit would suggest but I'm only now checking them all in =P
Remove old rspec files.
Add new development dependencies in gemspec
Add feature tests for permalinks.
Add feature tests for file conversion.
Add feature tests for layouts.
Add feature tests for partials.
Add feature tests for stylesheets inclusion.
Add feature tests for javascripts inclusion.
Add feature tests for themes cascade.
Add feature tests for pagination.
Add feature tests for tags.
Add feature tests for categories.
Add feature tests for drafts.
Add feature tests for data.
Add feature tests for summary.