use ::File::SEPARATOR and top level ::File classes within chef recipes

Hello!

I noticed while trying to do a chef-rewind on one of the template resources that the resource was called template[etc/init.d/wildfly] without the leading slash.  I know that chef solo and client are really changing directories internally to root when they run, but it might be better to use the full path name in these template resources as I got confused when my chef-rewind of template[/etc/init.d/wildfly] kept complaining that the resource wasn't found.  :)

Also, when using File.join's and other Ruby File class methods in chef code, I think the common practice is to use the ::File notation since Chef has a File class as well as ruby, and using ::File specifically uses ruby's.  I read about that practice here:

http://www.getchef.com/blog/2013/09/04/demystifying-common-idioms-in-chef-recipes/

Great cookbook and thank you for opening it up to the community!