End to end test
Adds tests that mimic 3 of the "cmb-target-problems" provided by LANL (prob1a, prob1b, prob3). Each test:
- generates an smtk attribute resource from yml specification, then
- generates the Truchas input file using the smtk export operator, then
- compares the output with a baseline file.
The current tests only cover heat transfer. Tests are still needed to cover induction heating and enclosure radiation.
This MR adds git submodules for the cmb-target-problems and smtk-tools repos.