improve package resource on windows

[chris-rock]

The current package resource is reported to be very slow Windows:

describe package('Orca') do
  it { should be_installed }      
end

This code should be improved: https://github.com/chef/inspec/blob/master/lib/resources/package.rb#L187-L209 and we should not require wmi

[chris-rock]

also reported via http://stackoverflow.com/questions/38972490/inspec-commands-are-too-slow-in-windows-am-i-missing-any-steps

[chris-rock]

As reference, specinfra is using registry only: https://github.com/mizzy/specinfra/blob/2cb5d3593f167c828e0213c3a50e9d7aaa1baa7c/lib/specinfra/backend/powershell/support/find_installed_application.ps1