Implement `berks package`

- Fixes #509
Make name attribute optional
Use a custom formatter for package. NullFormater for specs
Read chefignore, unless explicitly told not to
Don't use root_chefignore
Use a common method to define the formatting methods
Fix Null Formatter. Add specs
Use fixture repo in apply_command.feature
Use fixture repo in contingent_command.feature
Default locations are still broken
Bug Fix: tar files aren't read
Use fixture repo in groups_install.feature
Use fixture repo in info_command.feature
Use fixture repo in install_command.feature
Remove debugging output from CommunityRest
Use fixture repo in json_formatter.feature
Use fixture repo in list_command.feature
Use fixture repo in lockfile.feature
Use fixture repo in outdated_command.feature
Use fixture repo in show_command.feature