v.io/jiri/runutil: remove unnecessary layered 'run' methods.
v.io/jiri/runutil: remove unnecessary layered 'run' methods.

MultiPart: 2/2
Change-Id: I827d90f9235c31f64fb475776a63c087324a03ea

vanadium/go.devtools,vanadium/go.devtools,vanadium/go.devtools