Create remote_directory resource

[k0kubun]

Add remote_directory resource for itamae.
This is implemented with specinfra's send_directory command mizzy/specinfra#283.

Sending some grouped files by remote_file is boring, so this resource is useful in such a case.
I think this is a basic resource, but I'll close this PR and gemify it if it is not suitable as built-in resource.

example

remote_directory '/foo/bar/baz' do
  source 'hoge'
  owner  'root'
  group  'root'
  mode   '755'
  action :create
end

[ryotarai]

Thank you!

[ryotarai]

Released in v1.1.1