Fix shell provisioner to run with new machine abstraction

plugins/provisioners/shell/provisioner.rb

@@ -76,11 +76,12 @@ module VagrantPlugins
         command = "chmod +x #{config.upload_path} && #{config.upload_path}#{args}"
 
         with_script_file do |path|
-          # Upload the script to the VM
-          env[:vm].channel.upload(path.to_s, config.upload_path)
+          # Upload the script to the machine
+          env[:machine].communicate.tap do |comm|
+            comm.upload(path.to_s, config.upload_path)
 
             # Execute it with sudo
-          env[:vm].channel.sudo(command) do |type, data|
+            comm.sudo(command) do |type, data|
               if [:stderr, :stdout].include?(type)
                 # Output the data with the proper color based on the stream.
                 color = type == :stdout ? :green : :red
@@ -94,4 +95,5 @@ module VagrantPlugins
         end
       end
     end
+  end
 end