Fix #3 update kitchen-vagrant gem
Move final product to .products (was .rpmbuild)

- move final product to .products (was .rpmbuild)
- remove dependency on cookbook build-essential
- update examples accordingly
Add separators, optional virtualbox provider
Clean up README
Remind user about .kitchen.yml overrides
Clean up example descriptions
Constrain cookbook yum-epel to current version
Merge pull request #6 from 4-20ma/issue_3_update_kitchen_vagrant_gem

Fix #3 update kitchen-vagrant gem