Add rubocop syntax file check.
Fixed Gemspec
- Syntax fixes
- Added dependency on nokogiri 1.5.5 to avoid issue with rbvmomi
	(https://github.com/vmware/rbvmomi/issues/31)
Upgraded sync_folders to work with Vagrant 1.4+ (ported from vagrant_aws)
Code cleaning for plugin definition / builders.
Fixed syntax and error I18n.
final pass of first code cleanup
- fixed syntax
- wrapped everything to 80 columns
- changed rubocop config file to match coding style
Merge branch 'feature/code-cleaning' into develop