add sudo support to scriptfile

The following command employing a scriptfile will execute as the resource model's target user matching the tag criteria:

dispatch -L -p wsgc -I tags=pb+devint -s /local/path/to/rerun.bin -- stubbs: add-module -m foo --description bar

This command does this as a sudo user where sudo-command-enabled support has been added in resource model:

dispatch -L -p wsgc -I tags=pb+devint -- sudo -u tomcat /tmp/rerun.bin stubbs: add-module -m foo --description bar

It would be great to see a blending of the two (NOTE the following communicates the intent, option syntax not the key here):

dispatch -u tomcat -L -p wsgc -I tags=pb+devint -s /local/path/to/rerun.bin -- stubbs: add-module -m foo --description bar

where "-u tomcat" instructs the dispatcher to implicitly execute the scriptfile as a sudo to tomcat.