Replace super references with self references in AppFuture (#1199)
Replace super references with self references in AppFuture (#1199)

The behaviour shouldn't change over this commit as the self methods should
be the same as the super methods at present, but super() calls
should be avoided unless something specific is being done with inheritence.
Parsl/parsl,Parsl/parsl,Parsl/parsl,Parsl/parsl