Add an example of using output from one program as input to another

[mattwelborn]

Is your feature request related to a problem? Please describe.
A key goal of QCArchive is to promote interop between different programs, and to discourage creation of monoliths.

Describe the solution you'd like
An example where the output of one program is used to enable another program. Some ideas:

• Optimized DFT geometry from prog1 is loaded into prog2 for WF calculation.
• SAD guess (or converged orbitals) from prog1 is loaded into prog2.