Is your feature request related to a problem? Please describe.
It's difficult to scale a selection in WorldEdit, as //deform requires you to select the destination region, not the stuff you want to scale. Additionally, other transforms require you to first copy/cut the stuff to your clipboard, do the transform, and then paste.

Describe the solution you'd like

1. //scale added, with either size or x,y,z axes as parameters.
   AND
2. Scale should be added in a way consistent with //rotate and //flip, but all the transform commands as a whole should be able to operate on your selection too, perhaps as //cmd -s or similar.

Describe alternatives you've considered
See related problem.