Add support for FreeBSD next generation package manager
Refactor FreeBSD package providers
Refactor resolving of Freebsd package provider
Access source instance variable directly when setting provider
CHEF-5092: chef_gem should use omnibus `gem` binary
Rebase and update contribution info.
Merge branch 'freebsdPkgngSupport' of github.com:liseki/chef

Conflicts:
	lib/chef/platform/provider_mapping.rb
Merge pull request #1300 from opscode/lcg/CHEF-5092

CHEF-5092: chef_gem should use omnibus `gem` binary
Contribution info for CHEF-4637.
Merge branch 'master' into sersut/CHEF-4637

Conflicts:
	CHANGELOG.md
Merge pull request #1421 from opscode/sersut/CHEF-4637

CHEF-4637 - Add support for the new generation FreeBSD package manager