set class attr defaults; extract du to sep method
set class attr defaults; extract du to sep method

the du command is placed in a separate method so we can more easily test
via unit tests later

defaults for dir size and timeout are set on class methods appropriately

these methods should eventually move there way out of osc-jobconstructor
into ood_appkit or osc-machete

OSC/ood-myjobs,OSC/ood-myjobs,OSC/ood-myjobs,OSC/ood-myjobs